Method for controlling transmission power by terminal in narrowband wireless communication system, and terminal

ABSTRACT

A method for controlling, by a user equipment (UE), a transmit power in a narrowband (NB) wireless communication system is disclosed. The method includes receiving, from a base station, a preconfigured uplink (UL) resource (PUR) configuration, transmitting, to the base station, uplink data on the PUR, and receiving, from the base station, feedback information for the uplink data. A transmit power of the uplink data is controlled based on a number of receptions of the feedback information.

TECHNICAL FIELD

The present disclosure relates to a method of controlling, by a userequipment (UE), transmit power in a narrowband (NB) wirelesscommunication system, and a UE.

BACKGROUND ART

A mobile communication system has been developed to provide a voiceservice while ensuring the activity of a user. However, the area of themobile communication system has extended to a data service in additionto a voice. Due to the current explosive increase in traffic, there is ashortage of resources, and thus users demand a higher speed service.Accordingly, there is a need for a more advanced mobile communicationsystem.

Requirements for a next-generation mobile communication system need toable to support the accommodation of explosive data traffic, a dramaticincrease in the data rate per user, the accommodation of a significantincrease in the number of connected devices, very low end-to-endlatency, and high-energy efficiency. To this end, various technologies,such as dual connectivity, massive multiple input multiple output(MIMO), in-band full duplex, non-orthogonal multiple access (NOMA),super wideband support, and device networking, are researched.

DISCLOSURE Technical Problem

The present disclosure provides a method of controlling, by a userequipment (UE), transmit power in a narrowband (NB) wirelesscommunication system.

The technical objects to be achieved by the present disclosure are notlimited to those that have been described hereinabove merely by way ofexample, and other technical objects that are not mentioned can beclearly understood by those skilled in the art, to which the presentdisclosure pertains, from the following descriptions.

Technical Solution

In one aspect, there is provided a method for controlling, by a userequipment (UE), a transmit power in a narrowband (NB) wirelesscommunication system, the method comprising receiving, from a basestation, a preconfigured uplink (UL) resource (PUR) configuration;transmitting, to the base station, uplink data on the PUR; andreceiving, from the base station, feedback information for the uplinkdata, wherein a transmit power of the uplink data is controlled based ona number of receptions of the feedback information.

A ramping interval of the transmit power may be indicated from the basestation.

The UE may transmit the uplink data in an idle mode.

The transmit power may be a transmit power used in a connected mode withthe base station before entering the idle mode.

A specific offset value may be added to a current transmit power.

The transmit power of the uplink data may be controlled based on anumber of transmissions of the uplink data.

Advantageous Effects

According to the present disclosure, a user equipment (UE) of anarrowband (NB) wireless communication system can minimize an amount ofbattery consumed to receive ACK/NACK for data transmitted to a basestation.

Effects that could be achieved with the present disclosure are notlimited to those that have been described hereinabove merely by way ofexample, and other effects and advantages of the present disclosure willbe more clearly understood from the following description by a personskilled in the art to which the present disclosure pertains.

DESCRIPTION OF DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the present disclosure and constitute a part of thedetailed description, illustrate embodiments of the present disclosureand serve to explain technical features of the present disclosuretogether with the description.

FIG. 1 illustrates an example of 5G scenario to which the presentdisclosure is applicable.

FIG. 2 illustrates an AI device 100 according to an embodiment of thepresent disclosure.

FIG. 3 illustrates an AI server 200 according to an embodiment of thepresent disclosure.

FIG. 4 illustrates an AI system 1 according to an embodiment of thepresent disclosure.

FIG. 5 illustrates an example of LTE radio frame structure.

FIG. 6 illustrates an example of a resource grid for a downlink slot.

FIG. 7 illustrates an example of a downlink subframe structure.

FIG. 8 illustrates an example of an uplink subframe structure.

FIG. 9 illustrates an example of frame structure type 1.

FIG. 10 illustrates another example of frame structure type 2.

FIG. 11 illustrates an example of a random access symbol group.

FIG. 12 is a flow chart illustrating an initial access procedure inrelation to a radio system supporting a narrowband internet of thingssystem.

FIG. 13 is a flow chart illustrating a random access procedure inrelation to a radio system supporting a narrowband internet of thingssystem.

FIG. 14 illustrates a narrowband physical random access channel (NPRACH)region in relation to a radio system supporting a narrowband internet ofthings system.

FIG. 15 illustrates an example of a discontinuous reception (DRX) schemein an idle state and/or an inactive state.

FIG. 16 illustrates an example of a DRX cycle.

FIG. 17 illustrates a general system regarding a system informationacquisition procedure.

FIG. 18 illustrates an example of an operation flow chart of a UEperforming an idle mode preconfigured UL resource transmission of one ormore physical channels/signals to which a method described in thepresent disclosure is applicable.

FIG. 19 illustrates an example of an operation flow chart of a basestation performing an idle mode preconfigured UL resource transmissionof one or more physical channels/signals to which a method described inthe present disclosure is applicable.

FIG. 20 illustrates an example of signalling between a UE and a basestation performing idle mode preconfigured UL resourcetransmission/reception of one or more physical channels/signals to whicha method described in the present disclosure is applicable.

FIG. 21 illustrates a block configuration diagram of a wirelesscommunication device to which methods described in the presentdisclosure are applicable.

FIG. 22 illustrates a method of multiplexing different PURs andACK/NACK.

FIG. 23 is a flow chart illustrating a method for a UE to receive afeedback from a base station in a wireless communication systemsupporting narrowband (NB)-Internet of Things (IoT) according to anembodiment of the present disclosure.

FIG. 24 is a flow chart illustrating a method for a base station totransmit a feedback to a UE in a wireless communication systemsupporting NB-IoT according to an embodiment of the present disclosure.

FIG. 25 illustrates a communication system 1 applied to the presentdisclosure.

FIG. 26 illustrates a wireless device applicable to the presentdisclosure.

FIG. 27 illustrates a signal processing circuit for a transmissionsignal.

FIG. 28 illustrates another example of a wireless device applied to thepresent disclosure, and the wireless device can be implemented invarious types according to use-example/service.

FIG. 29 illustrates a portable device applied to the present disclosure.

FIG. 30 illustrates a robot applied to the present disclosure.

MODE FOR INVENTION

Reference will now be made in detail to implementations of thedisclosure, examples of which are illustrated in the accompanyingdrawings. A detailed description to be disclosed below together with theaccompanying drawing is to describe exemplary implementations of thepresent disclosure and not to describe a unique implementation forcarrying out the present disclosure. The detailed description belowincludes details to provide a complete understanding of the presentdisclosure. However, those skilled in the art know that the presentdisclosure can be carried out without the details.

In some cases, in order to prevent a concept of the present disclosurefrom being ambiguous, known structures and devices may be omitted orillustrated in a block diagram format based on core functions of eachstructure and device.

In the present disclosure, a base station (BS) means a terminal node ofa network directly performing communication with a terminal. In thepresent disclosure, specific operations described to be performed by thebase station may be performed by an upper node of the base station, ifnecessary or desired. That is, it is obvious that in the networkconsisting of multiple network nodes including the base station, variousoperations performed for communication with the terminal can beperformed by the base station or network nodes other than the basestation. The ‘base station (BS)’ may be replaced with terms such as afixed station, Node B, evolved-NodeB (eNB), a base transceiver system(BTS), an access point (AP), gNB (general NB), and the like. Further, a‘terminal’ may be fixed or movable and may be replaced with terms suchas user equipment (UE), a mobile station (MS), a user terminal (UT), amobile subscriber station (MSS), a subscriber station (SS), an advancedmobile station (AMS), a wireless terminal (WT), a machinetypecommunication (MTC) device, a machine-to-machine (M2M) device, adevice-to device (D2D) device, and the like.

In the present disclosure, downlink (DL) means communication from thebase station to the terminal, and uplink (UL) means communication fromthe terminal to the base station. In the downlink, a transmitter may bea part of the base station, and a receiver may be a part of theterminal. In the uplink, the transmitter may be a part of the terminal,and the receiver may be a part of the base station.

Specific terms used in the following description are provided to helpthe understanding of the present disclosure, and may be changed to otherforms within the scope without radio service (GPRS)/enhanced data ratesfor GSM evolution (EDGE).

The OFDMA may be implemented as radio technology such as IEEE 802.11(Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, E-UTRA (evolved UTRA), andthe like. The UTRA is a part of a universal mobile telecommunicationsystem (UMTS). 3rd generation partnership project (3GPP) long termevolution (LTE), as a part of an evolved UMTS (E-UMTS) using EUTRA,adopts the OFDMA in the downlink and the SC-FDMA in the uplink. LTE-A(advanced) is the evolution of 3GPP LTE.

Further, 5G new radio (NR) defines enhanced mobile broadband (eMBB),massive machine type communications (mMTC), ultra-reliable and lowlatency communications (URLLC), and vehicle-to-everything (V2X) based onusage scenario.

A 5G NR standard is divided into standalone (SA) and non-standalone(NSA) depending on co-existence between a NR system and a LTE system.

The 5G NR supports various subcarrier spacings and supports CP-OFDM inthe downlink and CP-OFDM and DFT-s-OFDM (SC-OFDM) in the uplink.

Implementations of the present disclosure can be supported by standarddocuments disclosed in at least one of IEEE 802, 3GPP, and 3GPP2 whichare the wireless access systems. That is, steps or parts inimplementations of the present disclosure which are not described toclearly show the technical spirit of the present disclosure can bedescribed by the standard document.

3GPP LTE/LTE-A/New RAT (NR) is primarily described for cleardescription, but technical features of the present disclosure are notlimited thereto.

In the present disclosure, ‘A and/or B’ may be interpreted in the samesense as ‘including at least one of A or B’.

Below, we describe an example of 5G use scenarios in which the methodproposed in this specification may apply.

Three major requirement areas of 5G include (1) an enhanced mobilebroadband (eMBB) area, (2) a massive machine type communication (mMTC)area and (3) an ultra-reliable and low latency communications (URLLC)area.

Some use cases may require multiple areas for optimization, and otheruse case may be focused on only one key performance indicator (KPI). 5Gsupport such various use cases in a flexible and reliable manner.

eMBB is far above basic mobile Internet access and covers media andentertainment applications in abundant bidirectional tasks, cloud oraugmented reality. Data is one of key motive powers of 5G, and dedicatedvoice services may not be first seen in the 5G era. In 5G, it isexpected that voice will be processed as an application program using adata connection simply provided by a communication system. Major causesfor an increased traffic volume include an increase in the content sizeand an increase in the number of applications that require a high datatransfer rate. Streaming service (audio and video), dialogue type videoand mobile Internet connections will be used more widely as more devicesare connected to the Internet. Such many application programs requireconnectivity always turned on in order to push real-time information andnotification to a user. A cloud storage and application suddenlyincreases in the mobile communication platform, and this may be appliedto both business and entertainment. Furthermore, cloud storage is aspecial use case that tows the growth of an uplink data transfer rate.5G is also used for remote business of cloud. When a tactile interfaceis used, further lower end-to-end latency is required to maintainexcellent user experiences. Entertainment, for example, cloud game andvideo streaming are other key elements which increase a need for themobile broadband ability. Entertainment is essential in the smartphoneand tablet anywhere including high mobility environments, such as atrain, a vehicle and an airplane. Another use case is augmented realityand information search for entertainment. In this case, augmentedreality requires very low latency and an instant amount of data.

Furthermore, one of the most expected 5G use case relates to a functioncapable of smoothly connecting embedded sensors in all fields, that is,mMTC. Until 2020, it is expected that potential IoT devices will reach20.4 billions. The industry IoT is one of areas in which 5G performsmajor roles enabling smart city, asset tracking, smart utility,agriculture and security infra.

URLLC includes a new service which will change the industry throughremote control of major infra and a link having ultra reliability/lowavailable latency, such as a self-driving vehicle. A level ofreliability and latency is essential for smart grid control, industryautomation, robot engineering, drone control and adjustment.

Multiple use cases are described more specifically.

5G may supplement fiber-to-the-home (FTTH) and cable-based broadband (orDOCSIS) as means for providing a stream evaluated from gigabits persecond to several hundreds of mega bits per second. Such fast speed isnecessary to deliver TV with resolution of 4K or more (6K, 8K or more)in addition to virtual reality and augmented reality. Virtual reality(VR) and augmented reality (AR) applications include immersive sportsgames. A specific application program may require a special networkconfiguration. For example, in the case of VR game, in order for gamecompanies to minimize latency, a core server may need to be integratedwith the edge network server of a network operator.

An automotive is expected to be an important and new motive power in 5G,along with many use cases for the mobile communication of an automotive.For example, entertainment for a passenger requires a high capacity anda high mobility mobile broadband at the same time. The reason for thisis that future users continue to expect a high-quality connectionregardless of their location and speed. Another use example of theautomotive field is an augmented reality dashboard. The augmentedreality dashboard overlaps and displays information, identifying anobject in the dark and notifying a driver of the distance and movementof the object, over a thing seen by the driver through a front window.In the future, a wireless module enables communication betweenautomotives, information exchange between an automotive and a supportedinfrastructure, and information exchange between an automotive and otherconnected devices (e.g., devices accompanied by a pedestrian). A safetysystem guides alternative courses of a behavior so that a driver candrive more safely, thereby reducing a danger of an accident. A next stepwill be a remotely controlled or self-driven vehicle. This requires veryreliable, very fast communication between different self-driven vehiclesand between an automotive and infra. In the future, a self-drivenvehicle may perform all driving activities, and a driver will be focusedon things other than traffic, which cannot be identified by anautomotive itself. Technical requirements of a self-driven vehiclerequire ultra-low latency and ultra-high speed reliability so thattraffic safety is increased up to a level which cannot be achieved by aperson.

A smart city and smart home mentioned as a smart society will beembedded as a high-density radio sensor network. The distributed networkof intelligent sensors will identify the cost of a city or home and acondition for energy-efficient maintenance. A similar configuration maybe performed for each home. All of a temperature sensor, a window andheating controller, a burglar alarm and home appliances are wirelesslyconnected. Many of such sensors are typically a low data transfer rate,low energy and a low cost. However, for example, real-time HD video maybe required for a specific type of device for surveillance.

The consumption and distribution of energy including heat or gas arehighly distributed and thus require automated control of a distributedsensor network. A smart grid collects information, and interconnectssuch sensors using digital information and a communication technology sothat the sensors operate based on the information. The information mayinclude the behaviors of a supplier and consumer, and thus the smartgrid may improve the distribution of fuel, such as electricity, in anefficient, reliable, economical, production-sustainable and automatedmanner. The smart grid may be considered to be another sensor networkhaving small latency.

A health part owns many application programs which reap the benefits ofmobile communication. A communication system can support remotetreatment providing clinical treatment at a distant place. This helps toreduce a barrier for the distance and can improve access to medicalservices which are not continuously used at remote farming areas.Furthermore, this is used to save life in important treatment and anemergency condition. A radio sensor network based on mobilecommunication can provide remote monitoring and sensors for parameters,such as the heart rate and blood pressure.

Radio and mobile communication becomes increasingly important in theindustry application field. Wiring requires a high installation andmaintenance cost. Accordingly, the possibility that a cable will bereplaced with reconfigurable radio links is an attractive occasion inmany industrial fields. However, to achieve the possibility requiresthat a radio connection operates with latency, reliability and capacitysimilar to those of the cable and that management is simplified. Lowlatency and a low error probability is a new requirement for aconnection to 5G.

Logistics and freight tracking is an important use case for mobilecommunication, which enables the tracking inventory and packagesanywhere using a location-based information system. The logistics andfreight tracking use case typically requires a low data speed, but awide area and reliable location information.

5G Scenario

Three major requirement areas of 5G include (1) an enhanced mobilebroadband (eMBB) area, (2) a massive machine type communication (mMTC)area and (3) an ultra-reliable and low latency communications (URLLC)area.

Some use cases may require multiple areas for optimization, and otheruse case may be focused on only one key performance indicator (KPI). 5Gsupport such various use cases in a flexible and reliable manner.

eMBB is far above basic mobile Internet access and covers media andentertainment applications in abundant bidirectional tasks, cloud oraugmented reality. Data is one of key motive powers of 5G, and dedicatedvoice services may not be first seen in the 5G era. In 5G, it isexpected that voice will be processed as an application program using adata connection simply provided by a communication system. Major causesfor an increased traffic volume include an increase in the content sizeand an increase in the number of applications that require a high datatransfer rate. Streaming service (audio and video), dialogue type videoand mobile Internet connections will be used more widely as more devicesare connected to the Internet. Such many application programs requireconnectivity always turned on in order to push real-time information andnotification to a user. A cloud storage and application suddenlyincreases in the mobile communication platform, and this may be appliedto both business and entertainment. Furthermore, cloud storage is aspecial use case that tows the growth of an uplink data transfer rate.5G is also used for remote business of cloud. When a tactile interfaceis used, further lower end-to-end latency is required to maintainexcellent user experiences. Entertainment, for example, cloud game andvideo streaming are other key elements which increase a need for themobile broadband ability. Entertainment is essential in the smartphoneand tablet anywhere including high mobility environments, such as atrain, a vehicle and an airplane. Another use case is augmented realityand information search for entertainment. In this case, augmentedreality requires very low latency and an instant amount of data.

Furthermore, one of the most expected 5G use case relates to a functioncapable of smoothly connecting embedded sensors in all fields, that is,mMTC. Until 2020, it is expected that potential IoT devices will reach20.4 billions. The industry IoT is one of areas in which 5G performsmajor roles enabling smart city, asset tracking, smart utility,agriculture and security infra.

URLLC includes a new service which will change the industry throughremote control of major infra and a link having ultra reliability/lowavailable latency, such as a self-driving vehicle. A level ofreliability and latency is essential for smart grid control, industryautomation, robot engineering, drone control and adjustment.

Multiple use cases are described more specifically.

5G may supplement fiber-to-the-home (FTTH) and cable-based broadband (orDOCSIS) as means for providing a stream evaluated from gigabits persecond to several hundreds of mega bits per second. Such fast speed isnecessary to deliver TV with resolution of 4K or more (6K, 8K or more)in addition to virtual reality and augmented reality. Virtual reality(VR) and augmented reality (AR) applications include immersive sportsgames. A specific application program may require a special networkconfiguration. For example, in the case of VR game, in order for gamecompanies to minimize latency, a core server may need to be integratedwith the edge network server of a network operator.

An automotive is expected to be an important and new motive power in 5G,along with many use cases for the mobile communication of an automotive.For example, entertainment for a passenger requires a high capacity anda high mobility mobile broadband at the same time. The reason for thisis that future users continue to expect a high-quality connectionregardless of their location and speed. Another use example of theautomotive field is an augmented reality dashboard. The augmentedreality dashboard overlaps and displays information, identifying anobject in the dark and notifying a driver of the distance and movementof the object, over a thing seen by the driver through a front window.In the future, a wireless module enables communication betweenautomotives, information exchange between an automotive and a supportedinfrastructure, and information exchange between an automotive and otherconnected devices (e.g., devices accompanied by a pedestrian). A safetysystem guides alternative courses of a behavior so that a driver candrive more safely, thereby reducing a danger of an accident. A next stepwill be a remotely controlled or self-driven vehicle. This requires veryreliable, very fast communication between different self-driven vehiclesand between an automotive and infra. In the future, a self-drivenvehicle may perform all driving activities, and a driver will be focusedon things other than traffic, which cannot be identified by anautomotive itself. Technical requirements of a self-driven vehiclerequire ultra-low latency and ultra-high speed reliability so thattraffic safety is increased up to a level which cannot be achieved by aperson.

A smart city and smart home mentioned as a smart society will beembedded as a high-density radio sensor network. The distributed networkof intelligent sensors will identify the cost of a city or home and acondition for energy-efficient maintenance. A similar configuration maybe performed for each home. All of a temperature sensor, a window andheating controller, a burglar alarm and home appliances are wirelesslyconnected. Many of such sensors are typically a low data transfer rate,low energy and a low cost. However, for example, real-time HD video maybe required for a specific type of device for surveillance.

The consumption and distribution of energy including heat or gas arehighly distributed and thus require automated control of a distributedsensor network. A smart grid collects information, and interconnectssuch sensors using digital information and a communication technology sothat the sensors operate based on the information. The information mayinclude the behaviors of a supplier and consumer, and thus the smartgrid may improve the distribution of fuel, such as electricity, in anefficient, reliable, economical, production-sustainable and automatedmanner. The smart grid may be considered to be another sensor networkhaving small latency.

A health part owns many application programs which reap the benefits ofmobile communication. A communication system can support remotetreatment providing clinical treatment at a distant place. This helps toreduce a barrier for the distance and can improve access to medicalservices which are not continuously used at remote farming areas.Furthermore, this is used to save life in important treatment and anemergency condition. A radio sensor network based on mobilecommunication can provide remote monitoring and sensors for parameters,such as the heart rate and blood pressure.

Radio and mobile communication becomes increasingly important in theindustry application field. Wiring requires a high installation andmaintenance cost. Accordingly, the possibility that a cable will bereplaced with reconfigurable radio links is an attractive occasion inmany industrial fields. However, to achieve the possibility requiresthat a radio connection operates with latency, reliability and capacitysimilar to those of the cable and that management is simplified. Lowlatency and a low error probability is a new requirement for aconnection to 5G.

Logistics and freight tracking is an important use case for mobilecommunication, which enables the tracking inventory and packagesanywhere using a location-based information system. The logistics andfreight tracking use case typically requires a low data speed, but awide area and reliable location information.

Artificial Intelligence (AI)

Artificial intelligence means the field in which artificial intelligenceor methodology capable of producing artificial intelligence isresearched. Machine learning means the field in which various problemshandled in the artificial intelligence field are defined and methodologyfor solving the problems are researched. Machine learning is alsodefined as an algorithm for improving performance of a task throughcontinuous experiences for the task.

An artificial neural network (ANN) is a model used in machine learning,and is configured with artificial neurons (nodes) forming a networkthrough a combination of synapses, and may mean the entire model havinga problem-solving ability. The artificial neural network may be definedby a connection pattern between the neurons of different layers, alearning process of updating a model parameter, and an activationfunction for generating an output value.

The artificial neural network may include an input layer, an outputlayer, and optionally one or more hidden layers. Each layer includes oneor more neurons. The artificial neural network may include a synapseconnecting neurons. In the artificial neural network, each neuron mayoutput a function value of an activation function for input signals,weight, and a bias input through a synapse.

A model parameter means a parameter determined through learning, andincludes the weight of a synapse connection and the bias of a neuron.Furthermore, a hyper parameter means a parameter that needs to beconfigured prior to learning in the machine learning algorithm, andincludes a learning rate, the number of times of repetitions, amini-deployment size, and an initialization function.

An object of the training of the artificial neural network may beconsidered to determine a model parameter that minimizes a lossfunction. The loss function may be used as an index for determining anoptimal model parameter in the learning process of an artificial neuralnetwork.

Machine learning may be classified into supervised learning,unsupervised learning, and reinforcement learning based on a learningmethod.

Supervised learning means a method of training an artificial neuralnetwork in the state in which a label for learning data has been given.The label may mean an answer (or a result value) that must be deduced byan artificial neural network when learning data is input to theartificial neural network. Unsupervised learning may mean a method oftraining an artificial neural network in the state in which a label forlearning data has not been given. Reinforcement learning may mean alearning method in which an agent defined within an environment istrained to select a behavior or behavior sequence that maximizesaccumulated compensation in each state.

Machine learning implemented as a deep neural network (DNN) including aplurality of hidden layers, among artificial neural networks, is alsocalled deep learning. Deep learning is part of machine learning.Hereinafter, machine learning is used as a meaning including deeplearning.

<Robot>

A robot may mean a machine that automatically processes a given task oroperates based on an autonomously owned ability. Particularly, a robothaving a function for recognizing an environment and autonomouslydetermining and performing an operation may be called an intelligencetype robot.

A robot may be classified for industry, medical treatment, home, andmilitary based on its use purpose or field.

A robot includes a driving unit including an actuator or motor, and mayperform various physical operations, such as moving a robot joint.Furthermore, a movable robot includes a wheel, a brake, a propeller,etc. in a driving unit, and may run on the ground or fly in the airthrough the driving unit.

<Self-Driving or Autonomous-Driving>

Self-driving means a technology for autonomous driving. A self-drivingvehicle means a vehicle that runs without a user manipulation or by auser's minimum manipulation.

For example, self-driving may include all of a technology formaintaining a driving lane, a technology for automatically controllingspeed, such as adaptive cruise control, a technology for automaticdriving along a predetermined path, a technology for automaticallyconfiguring a path when a destination is set and driving.

A vehicle includes all of a vehicle having only an internal combustionengine, a hybrid vehicle including both an internal combustion engineand an electric motor, and an electric vehicle having only an electricmotor, and may include a train, a motorcycle, etc. in addition to thevehicles.

In this case, the self-driving vehicle may be considered to be a robothaving a self-driving function.

<Extended reality (XR)>

Extended reality collectively refers to virtual reality (VR), augmentedreality (AR), and mixed reality (MR). The VR technology provides anobject or background of the real world as a CG image only. The ARtechnology provides a virtually produced CG image on an actual thingimage. The MR technology is a computer graphics technology for mixingand combining virtual objects with the real world and providing them.

The MR technology is similar to the AR technology in that it shows areal object and a virtual object. However, in the AR technology, avirtual object is used in a form to supplement a real object. Incontrast, unlike in the AR technology, in the MR technology, a virtualobject and a real object are used as the same character.

The XR technology may be applied to a head-mount display (HMD), ahead-up display (HUD), a mobile phone, a tablet PC, a laptop, a desktop,TV, and a digital signage. A device to which the XR technology has beenapplied may be called an XR device.

FIG. 1 is an augmented reality electronic device based on the one-dayexample of this invention.

As shown in FIG. 1, electronic devices following the one example of thisinvention may include a frame (100), a control plane (200), and adisplay unit of display (300).

Electronic devices may be equipped with a glass type. Glass-typeelectronic devices are designed to be wearable to the head of the humanbody and may be equipped with a frame (case, housing, etc.) (100). Theframe (100) can be formed of flexible materials to facilitate wearing.

The frame (100) is supported on the head and provides room for variousparts. As indicated, the frame (100) may be equipped with electroniccomponents such as the control part (200), the user input part (130), orthe sound output part (140). In addition, the frame (100) can beequipped with removable lenses covering at least one of the left andright sides.

The frame (100) may have the appearance of glasses worn on the face ofthe user's body, as illustrated in the drawing, but not necessarilylimited to goggles worn close to the user's face.

Such a frame (100) may include a pair of side frames (120) thatintersect with the front frame (110) equipped with at least one openingand the first direction (y) that intersects the front frame (110).

The control department (200) is designed to control the variouselectronic components that are mounted on electronic devices.

The control plane (200) can generate images that are displayed to theuser or images that are continuous. The control plane (200) can includemultiple lenses, such as image source panels that generate images andmultiple lenses that diffuse and converge light generated from imagesource panels.

The control plane (200) can be fixed to either side frame (120). Forexample, a control plane (200) can be fixed to either side frame (120)inner or outer, or embedded inside any side frame (120) to form a whole.Alternatively, the control plane (200) may be fixed to the front frame(110) or set aside from the electronic device.

The display unit (300) can be implemented as a head mounted display(HMD). HMD is a display method that is mounted on a head and displaysimages directly in front of the user's eyes. When a user wears anelectronic device, the display unit (300) can be positionedcorresponding to at least one of the left or right eye, so that the usercan directly provide images in front of the user's eyes. In thisdrawing, the display part (300) is located in the corresponding part ofthe right eye so that the image can be output to the user's right eye.

The display part (300) allows the user to visually recognize theexternal environment, while simultaneously allowing the user to seeimages generated by the control part (200). For example, the displaypart (300) can project images into the display area using a prism.

And the display part (300) can be flood-resistant to allow the projectedimage and the general view (the range of the user's view through theeyes) to be seen simultaneously. For example, the display part (300) maybe translucent and form an optical element containing glass.

And the display part (300) may be inserted into the opening contained inthe front frame (110) and fixed, or located on the back of the openingdoor (i.e., between the opening and the user), and fixed to the frontframe (110). The drawings illustrate when the display part (300) ispositioned on the back of the opening, fixed to the front frame (110),whereas the display part (300) can be positioned and fixed in variouspositions on the frame (100).

The electronic device, as illustrated in FIG. 1, allows the image lightto be released to the other side through the display light, allowing theuser to see the image generated by the control light (200) when theimage light is applied to the display light (300).

Consequently, the user can view the external environment through theopening of the frame (100) while simultaneously viewing the imagesgenerated from the control plane (200). In other words, images outputthrough the display part (300) may appear overlap with normal vision.Electronic devices can leverage these display characteristics to provideaugmented reality (AR) in which virtual images are superimposed onreal-world images or backgrounds and shown as a single image.

FIG. 2 illustrates an AI device 100 according to an embodiment of thepresent disclosure.

The AI device 100 may be implemented as a stationary device or mobiledevice, such as TV, a projector, a mobile phone, a smartphone, a desktopcomputer, a notebook, a terminal for digital broadcasting, a personaldigital assistants (PDA), a portable multimedia player (PMP), anavigator, a tablet PC, a wearable device, a set-top box (STB), a DMBreceiver, a radio, a washing machine, a refrigerator, a desktopcomputer, digital signage, a robot, and a vehicle.

Referring to FIG. 2, a terminal 100 may include a communication unit110, an input unit 120, a learning processor 130, a sensing unit 140, anoutput unit 150, a memory 170 and a processor 180.

The communication unit 110 may transmit and receive data to and fromexternal devices, such as other AI devices 100 a to 100 e or an AIserver 200 using wired/wireless communication technologies. For example,the communication unit 110 may transmit and receive sensor information,user input, a learning model, or a control signal to and from externaldevices.

In this case, communication technologies used by the communication unit110 include a global system for mobile communication (GSM), codedivision multi access (CDMA), long term evolution (LTE), 5G, a wirelessLAN (WLAN), wireless-fidelity (Wi-Fi), Bluetooth™, radio frequencyidentification (RFID), infrared data association (IrDA), ZigBee, andnear field communication (NFC).

The input unit 120 may obtain various types of data.

In this case, the input unit 120 may include a camera for an imagesignal input, a microphone for receiving an audio signal, a user inputunit for receiving information from a user, etc. In this case, thecamera or the microphone is treated as a sensor, and a signal obtainedfrom the camera or the microphone may be called sensing data or sensorinformation.

The input unit 120 may obtain learning data for model learning and inputdata to be used when an output is obtained using a learning model. Theinput unit 120 may obtain not-processed input data. In this case, theprocessor 180 or the learning processor 130 may extract an input featureby performing pre-processing on the input data.

The learning processor 130 may be trained by a model configured with anartificial neural network using learning data. In this case, the trainedartificial neural network may be called a learning model. The learningmodel is used to deduce a result value of new input data not learningdata. The deduced value may be used as a base for performing a givenoperation.

In this case, the learning processor 130 may perform AI processing alongwith the learning processor 240 of the AI server 200.

In this case, the learning processor 130 may include memory integratedor implemented in the AI device 100. Alternatively, the learningprocessor 130 may be implemented using the memory 170, external memorydirectly coupled to the AI device 100 or memory maintained in anexternal device.

The sensing unit 140 may obtain at least one of internal information ofthe AI device 100, surrounding environment information of the AI device100, or user information using various sensors.

In this case, sensors included in the sensing unit 140 include aproximity sensor, an illumination sensor, an acceleration sensor, amagnetic sensor, a gyro sensor, an inertia sensor, an RGB sensor, an IRsensor, a fingerprint recognition sensor, an ultrasonic sensor, a photosensor, a microphone, a lidar, and a radar.

The output unit 150 may generate an output related to a visual sense, anauditory sense or a tactile sense.

In this case, the output unit 150 may include a display unit foroutputting visual information, a speaker for outputting auditoryinformation, and a haptic module for outputting tactile information.

The memory 170 may store data supporting various functions of the AIdevice 100. For example, the memory 170 may store input data obtained bythe input unit 120, learning data, a learning model, a learning history,etc.

The processor 180 may determine at least one executable operation of theAI device 100 based on information, determined or generated using a dataanalysis algorithm or a machine learning algorithm. Furthermore, theprocessor 180 may perform the determined operation by controllingelements of the AI device 100.

To this end, the processor 180 may request, search, receive, and use thedata of the learning processor 130 or the memory 170, and may controlelements of the AI device 100 to execute a predicted operation or anoperation determined to be preferred, among the at least one executableoperation.

In this case, if association with an external device is necessary toperform the determined operation, the processor 180 may generate acontrol signal for controlling the corresponding external device andtransmit the generated control signal to the corresponding externaldevice.

The processor 180 may obtain intention information for a user input andtransmit user requirements based on the obtained intention information.

In this case, the processor 180 may obtain the intention information,corresponding to the user input, using at least one of a speech to text(STT) engine for converting a voice input into a text string or anatural language processing (NLP) engine for obtaining intentioninformation of a natural language.

In this case, at least some of at least one of the STT engine or the NLPengine may be configured as an artificial neural network trained basedon a machine learning algorithm. Furthermore, at least one of the STTengine or the NLP engine may have been trained by the learning processor130, may have been trained by the learning processor 240 of the AIserver 200 or may have been trained by distributed processing thereof.

The processor 180 may collect history information including theoperation contents of the AI device 100 or the feedback of a user for anoperation, may store the history information in the memory 170 or thelearning processor 130, or may transmit the history information to anexternal device, such as the AI server 200. The collected historyinformation may be used to update a learning model.

The processor 180 may control at least some of the elements of the AIdevice 100 in order to execute an application program stored in thememory 170. Moreover, the processor 180 may combine and drive two ormore of the elements included in the AI device 100 in order to executethe application program.

FIG. 3 illustrates an AI server 200 according to an embodiment of thepresent disclosure.

Referring to FIG. 3, the AI server 200 may mean an apparatus whichtrains an artificial neural network using a machine learning algorithmor which uses a trained artificial neural network. In this case, the AIserver 200 is configured with a plurality of servers and may performdistributed processing and may be defined as a 5G network. In this case,the AI server 200 may be included as a partial configuration of the AIdevice 100, and may perform at least some of AI processing.

The AI server 200 may include a communication unit 210, memory 230, alearning processor 240 and a processor 260.

The communication unit 210 may transmit and receive data to and from anexternal device, such as the AI device 100.

The memory 230 may include a model storage unit 231. The model storageunit 231 may store a model (or artificial neural network 231 a) which isbeing trained or has been trained through the learning processor 240.

The learning processor 240 may train the artificial neural network 231 ausing learning data. The learning model may be used in the state inwhich it has been mounted on the AI server 200 of the artificial neuralnetwork or may be mounted on an external device, such as the AI device100, and used.

The learning model may be implemented as hardware, software or acombination of hardware and software. If some of or the entire learningmodel is implemented as software, one or more instructions configuringthe learning model may be stored in the memory 230.

The processor 260 may deduce a result value of new input data using thelearning model, and may generate a response or control command based onthe deduced result value.

FIG. 4 illustrates an AI system 1 according to an embodiment of thepresent disclosure.

Referring to FIG. 4, the AI system 1 is connected to at least one of theAI server 200, a robot 100 a, a self-driving vehicle 100 b, an XR device100 c, a smartphone 100 d or home appliances 100 e over a cloud network10. In this case, the robot 100 a, the self-driving vehicle 100 b, theXR device 100 c, the smartphone 100 d or the home appliances 100 e towhich the AI technology has been applied may be called AI devices 100 ato 100 e.

The cloud network 10 may configure part of cloud computing infra or maymean a network present within cloud computing infra. In this case, thecloud network 10 may be configured using the 3G network, the 4G or longterm evolution (LTE) network or the 5G network.

That is, the devices 100 a to 100 e (200) configuring the AI system 1may be interconnected over the cloud network 10. Particularly, thedevices 100 a to 100 e and 200 may communicate with each other through abase station, but may directly communicate with each other without theintervention of a base station.

The AI server 200 may include a server for performing AI processing anda server for performing calculation on big data.

The AI server 200 is connected to at least one of the robot 100 a, theself-driving vehicle 100 b, the XR device 100 c, the smartphone 100 d orthe home appliances 100 e, that is, AI devices configuring the AI system1, over the cloud network 10, and may help at least some of the AIprocessing of the connected AI devices 100 a to 100 e.

In this case, the AI server 200 may train an artificial neural networkbased on a machine learning algorithm in place of the AI devices 100 ato 100 e, may directly store a learning model or may transmit thelearning model to the AI devices 100 a to 100 e.

In this case, the AI server 200 may receive input data from the AIdevices 100 a to 100 e, may deduce a result value of the received inputdata using the learning model, may generate a response or controlcommand based on the deduced result value, and may transmit the responseor control command to the AI devices 100 a to 100 e.

Alternatively, the AI devices 100 a to 100 e may directly deduce aresult value of input data using a learning model, and may generate aresponse or control command based on the deduced result value.

Hereinafter, various embodiments of the AI devices 100 a to 100 e towhich the above-described technology is applied are described. In thiscase, the AI devices 100 a to 100 e shown in FIG. 4 may be considered tobe detailed embodiments of the AI device 100 shown in FIG. 2.

<AI+Robot>

An AI technology is applied to the robot 100 a, and the robot 100 a maybe implemented as a guidance robot, a transport robot, a cleaning robot,a wearable robot, an entertainment robot, a pet robot, an unmannedflight robot, etc.

The robot 100 a may include a robot control module for controlling anoperation. The robot control module may mean a software module or a chipin which a software module has been implemented using hardware.

The robot 100 a may obtain state information of the robot 100 a, maydetect (recognize) a surrounding environment and object, may generatemap data, may determine a moving path and a running plan, may determinea response to a user interaction, or may determine an operation usingsensor information obtained from various types of sensors.

In this case, the robot 100 a may use sensor information obtained by atleast one sensor among a lidar, a radar, and a camera in order todetermine the moving path and running plan.

The robot 100 a may perform the above operations using a learning modelconfigured with at least one artificial neural network. For example, therobot 100 a may recognize a surrounding environment and object using alearning model, and may determine an operation using recognizedsurrounding environment information or object information. In this case,the learning model may have been directly trained in the robot 100 a ormay have been trained in an external device, such as the AI server 200.

In this case, the robot 100 a may directly generate results using thelearning model and perform an operation, but may perform an operation bytransmitting sensor information to an external device, such as the AIserver 200, and receiving results generated in response thereto.

The robot 100 a may determine a moving path and running plan using atleast one of map data, object information detected from sensorinformation, or object information obtained from an external device. Therobot 100 a may run along the determined moving path and running plan bycontrolling the driving unit.

The map data may include object identification information for variousobjects disposed in the space in which the robot 100 a moves. Forexample, the map data may include object identification information forfixed objects, such as a wall and a door, and movable objects, such as aflowerpot and a desk. Furthermore, the object identification informationmay include a name, a type, a distance, a location, etc.

Furthermore, the robot 100 a may perform an operation or run bycontrolling the driving unit based on a user's control/interaction. Inthis case, the robot 100 a may obtain intention information of aninteraction according to a user's behavior or voice speaking, maydetermine a response based on the obtained intention information, andmay perform an operation.

<AI+Self-Driving>

An AI technology is applied to the self-driving vehicle 100 b, and theself-driving vehicle 100 b may be implemented as a movable type robot, avehicle, an unmanned flight body, etc.

The self-driving vehicle 100 b may include a self-driving control modulefor controlling a self-driving function. The self-driving control modulemay mean a software module or a chip in which a software module has beenimplemented using hardware. The self-driving control module may beincluded in the self-driving vehicle 100 b as an element of theself-driving vehicle 100 b, but may be configured as separate hardwareoutside the self-driving vehicle 100 b and connected to the self-drivingvehicle 100 b.

The self-driving vehicle 100 b may obtain state information of theself-driving vehicle 100 b, may detect (recognize) a surroundingenvironment and object, may generate map data, may determine a movingpath and running plan, or may determine an operation using sensorinformation obtained from various types of sensors.

In this case, in order to determine the moving path and running plan,like the robot 100 a, the self-driving vehicle 100 b may use sensorinformation obtained from at least one sensor among LIDAR, a radar and acamera.

Particularly, the self-driving vehicle 100 b may recognize anenvironment or object in an area whose view is blocked or an area of agiven distance or more by receiving sensor information for theenvironment or object from external devices, or may directly receiverecognized information for the environment or object from externaldevices.

The self-driving vehicle 100 b may perform the above operations using alearning model configured with at least one artificial neural network.For example, the self-driving vehicle 100 b may recognize a surroundingenvironment and object using a learning model, and may determine theflow of running using recognized surrounding environment information orobject information. In this case, the learning model may have beendirectly trained in the self-driving vehicle 100 b or may have beentrained in an external device, such as the AI server 200.

In this case, the self-driving vehicle 100 b may directly generateresults using the learning model and perform an operation, but mayperform an operation by transmitting sensor information to an externaldevice, such as the AI server 200, and receiving results generated inresponse thereto.

The self-driving vehicle 100 b may determine a moving path and runningplan using at least one of map data, object information detected fromsensor information or object information obtained from an externaldevice. The self-driving vehicle 100 b may run based on the determinedmoving path and running plan by controlling the driving unit.

The map data may include object identification information for variousobjects disposed in the space (e.g., road) in which the self-drivingvehicle 100 b runs. For example, the map data may include objectidentification information for fixed objects, such as a streetlight, arock, and a building, etc., and movable objects, such as a vehicle and apedestrian. Furthermore, the object identification information mayinclude a name, a type, a distance, a location, etc.

Furthermore, the self-driving vehicle 100 b may perform an operation ormay run by controlling the driving unit based on a user'scontrol/interaction. In this case, the self-driving vehicle 100 b mayobtain intention information of an interaction according to a user′behavior or voice speaking, may determine a response based on theobtained intention information, and may perform an operation.

<AI+XR>

An AI technology is applied to the XR device 100 c, and the XR device100 c may be implemented as a head-mount display, a head-up displayprovided in a vehicle, television, a mobile phone, a smartphone, acomputer, a wearable device, home appliances, a digital signage, avehicle, a fixed type robot or a movable type robot.

The XR device 100 c may generate location data and attributes data forthree-dimensional points by analyzing three-dimensional point cloud dataor image data obtained through various sensors or from an externaldevice, may obtain information on a surrounding space or real objectbased on the generated location data and attributes data, and may outputan XR object by rendering the XR object. For example, the XR device 100c may output an XR object, including additional information for arecognized object, by making the XR object correspond to thecorresponding recognized object.

The XR device 100 c may perform the above operations using a learningmodel configured with at least one artificial neural network. Forexample, the XR device 100 c may recognize a real object inthree-dimensional point cloud data or image data using a learning model,and may provide information corresponding to the recognized real object.In this case, the learning model may have been directly trained in theXR device 100 c or may have been trained in an external device, such asthe AI server 200.

In this case, the XR device 100 c may directly generate results using alearning model and perform an operation, but may perform an operation bytransmitting sensor information to an external device, such as the AIserver 200, and receiving results generated in response thereto.

<AI+Robot+Self-Driving>

An AI technology and a self-driving technology are applied to the robot100 a, and the robot 100 a may be implemented as a guidance robot, atransport robot, a cleaning robot, a wearable robot, an entertainmentrobot, a pet robot, an unmanned flight robot, etc.

The robot 100 a to which the AI technology and the self-drivingtechnology have been applied may mean a robot itself having aself-driving function or may mean the robot 100 a interacting with theself-driving vehicle 100 b.

The robot 100 a having the self-driving function may collectively referto devices that autonomously move along a given flow without control ofa user or autonomously determine a flow and move.

The robot 100 a and the self-driving vehicle 100 b having theself-driving function may use a common sensing method in order todetermine one or more of a moving path or a running plan. For example,the robot 100 a and the self-driving vehicle 100 b having theself-driving function may determine one or more of a moving path or arunning plan using information sensed through LIDAR, a radar, a camera,etc.

The robot 100 a interacting with the self-driving vehicle 100 b ispresent separately from the self-driving vehicle 100 b, and may performan operation associated with a self-driving function inside or outsidethe self-driving vehicle 100 b or associated with a user got in theself-driving vehicle 100 b.

In this case, the robot 100 a interacting with the self-driving vehicle100 b may control or assist the self-driving function of theself-driving vehicle 100 b by obtaining sensor information in place ofthe self-driving vehicle 100 b and providing the sensor information tothe self-driving vehicle 100 b, or by obtaining sensor information,generating surrounding environment information or object information,and providing the surrounding environment information or objectinformation to the self-driving vehicle 100 b.

Alternatively, the robot 100 a interacting with the self-driving vehicle100 b may control the function of the self-driving vehicle 100 b bymonitoring a user got in the self-driving vehicle 100 b or through aninteraction with a user. For example, if a driver is determined to be adrowsiness state, the robot 100 a may activate the self-driving functionof the self-driving vehicle 100 b or assist control of the driving unitof the self-driving vehicle 100 b. In this case, the function of theself-driving vehicle 100 b controlled by the robot 100 a may include afunction provided by a navigation system or audio system provided withinthe self-driving vehicle 100 b, in addition to a self-driving functionsimply.

Alternatively, the robot 100 a interacting with the self-driving vehicle100 b may provide information to the self-driving vehicle 100 b or mayassist a function outside the self-driving vehicle 100 b. For example,the robot 100 a may provide the self-driving vehicle 100 b with trafficinformation, including signal information, as in a smart traffic light,and may automatically connect an electric charger to a filling inletthrough an interaction with the self-driving vehicle 100 b as in theautomatic electric charger of an electric vehicle.

<AI+Robot+XR>

An AI technology and an XR technology are applied to the robot 100 a,and the robot 100 a may be implemented as a guidance robot, a transportrobot, a cleaning robot, a wearable robot, an entertainment robot, a petrobot, an unmanned flight robot, a drone, etc.

The robot 100 a to which the XR technology has been applied may mean arobot, that is, a target of control/interaction within an XR image. Inthis case, the robot 100 a is different from the XR device 100 c, andthey may operate in conjunction with each other.

When the robot 100 a, that is, a target of control/interaction within anXR image, obtains sensor information from sensors including a camera,the robot 100 a or the XR device 100 c may generate an XR image based onthe sensor information, and the XR device 100 c may output the generatedXR image. Furthermore, the robot 100 a may operate based on a controlsignal received through the XR device 100 c or a user's interaction.

For example, a user may identify a corresponding XR image at timing ofthe robot 100 a, remotely operating in conjunction through an externaldevice, such as the XR device 100 c, may adjust the self-driving path ofthe robot 100 a through an interaction, may control an operation ordriving, or may identify information of a surrounding object.

<AI+Self-Driving+XR>

An AI technology and an XR technology are applied to the self-drivingvehicle 100 b, and the self-driving vehicle 100 b may be implemented asa movable type robot, a vehicle, an unmanned flight body, etc.

The self-driving vehicle 100 b to which the XR technology has beenapplied may mean a self-driving vehicle equipped with means forproviding an XR image or a self-driving vehicle, that is, a target ofcontrol/interaction within an XR image. Particularly, the self-drivingvehicle 100 b, that is, a target of control/interaction within an XRimage, is different from the XR device 100 c, and they may operate inconjunction with each other.

The self-driving vehicle 100 b equipped with the means for providing anXR image may obtain sensor information from sensors including a camera,and may output an XR image generated based on the obtained sensorinformation. For example, the self-driving vehicle 100 b includes anHUD, and may provide a passenger with an XR object corresponding to areal object or an object within a screen by outputting an XR image.

In this case, when the XR object is output to the HUD, at least some ofthe XR object may be output with it overlapping a real object towardwhich a passenger's view is directed. In contrast, when the XR object isdisplayed on a display included within the self-driving vehicle 100 b,at least some of the XR object may be output so that it overlaps anobject within a screen. For example, the self-driving vehicle 100 b mayoutput XR objects corresponding to objects, such as a carriageway,another vehicle, a traffic light, a signpost, a two-wheeled vehicle, apedestrian, and a building.

When the self-driving vehicle 100 b, that is, a target ofcontrol/interaction within an XR image, obtains sensor information fromsensors including a camera, the self-driving vehicle 100 b or the XRdevice 100 c may generate an XR image based on the sensor information.The XR device 100 c may output the generated XR image. Furthermore, theself-driving vehicle 100 b may operate based on a control signalreceived through an external device, such as the XR device 100 c, or auser's interaction.

Overview of NB-IoT

NB-IoT technology is described below.

Overview of System

FIG. 5 illustrates an example of LTE radio frame structure.

In FIG. 5, a radio frame includes 10 subframes. A subframe includes twoslots in time domain. A time for transmitting one subframe is defined asa transmission time interval (TTI). For example, one subframe may have alength of 1 millisecond (ms), and one slot may have a length of 0.5 ms.One slot includes a plurality of orthogonal frequency divisionmultiplexing (OFDM) symbols in time domain. Since the 3GPP LTE uses theOFDMA in the downlink, the OFDM symbol is for representing one symbolperiod. The OFDM symbol may also be referred to as an SC-FDMA symbol ora symbol period. A resource block (RB) is a resource allocation unit,and includes a plurality of contiguous subcarriers in one slot. Thestructure of the radio frame is shown for exemplary purposes only. Thus,the number of subframes included in the radio frame, or the number ofslots included in the subframe, or the number of OFDM symbols includedin the slot may be modified in various manners.

FIG. 6 illustrates an example of a resource grid for a downlink slot.

In FIG. 6, a downlink slot includes a plurality of OFDM symbols in timedomain. The present disclosure is described herein by way of examplethat one downlink slot includes 7 OFDM symbols, and one resource block(RB) includes 12 subcarriers in frequency domain. However, the presentdisclosure is not limited thereto. Each element on a resource grid isreferred to as a resource element (RE). One RB includes 12×7 REs. Thenumber NDL of RBs included in the downlink slot depends on a downlinktransmit bandwidth. The structure of an uplink slot may be same as thestructure of the downlink slot.

FIG. 7 illustrates an example of a downlink subframe structure.

In FIG. 7, a maximum of three OFDM symbols located in a front portion ofa first slot within a subframe correspond to a control region to beassigned with a control channel. The remaining OFDM symbols correspondto a data region to be assigned with a physical downlink shared chancel(PDSCH). Examples of downlink control channels used in the 3GPP LTEincludes a physical control format indicator channel (PCFICH), aphysical downlink control channel (PDCCH), a physical hybrid ARQindicator channel (PHICH), etc. The PCFICH is transmitted at a firstOFDM symbol of a subframe and carries information regarding the numberof OFDM symbols used for transmission of control channels within thesubframe. The PHICH is a response of uplink transmission and carries anHARQ acknowledgment (ACK)/not-acknowledgment (NACK) signal. Controlinformation transmitted on the PDCCH is referred to as downlink controlinformation (DCI). The DCI includes uplink or downlink schedulinginformation or includes an uplink transmit (Tx) power control commandfor arbitrary UE groups.

The PDCCH may carry a transport format and a resource allocation of adownlink shared channel (DL-SCH), resource allocation information of anuplink shared channel (UL-SCH), paging information on a paging channel(PCH), system information on the DL-SCH, a resource allocation of anupper-layer control message such as a random access response transmittedon the PDSCH, a set of Tx power control commands on individual UEswithin an arbitrary UE group, a Tx power control command, activation ofa voice over IP (VoIP), etc. A plurality of PDCCHs can be transmittedwithin a control region. The UE can monitor the plurality of PDCCHs. ThePDCCH is transmitted on aggregation of one or several consecutivecontrol channel elements (CCEs). The CCE is a logical allocation unitused to provide the PDCCH with a coding rate based on a state of a radiochannel. The CCE corresponds to a plurality of resource element groups(REGs). A format of the PDCCH and the number of bits of the availablePDCCH are determined according to a correlation between the number ofCCEs and the coding rate provided by the CCEs. The BS determines a PDCCHformat according to DCI to be transmitted to the UE, and attaches acyclic redundancy check (CRC) to control information. The CRC is maskedwith a unique identifier (referred to as a radio network temporaryidentifier (RNTI)) according to an owner or usage of the PDCCH. If thePDCCH is for a specific UE, a unique identifier (e.g., cell-RNTI(C-RNTI)) of the UE may be masked to the CRC. For another example, ifthe PDCCH is for a paging message, a paging indicator identifier (e.g.,paging-RNTI (P-RNTI)) may be masked to the CRC. If the PDCCH is forsystem information (more specifically, a system information block (SIB)to be described below), a system information identifier and a systeminformation RNTI (SI-RNTI) may be masked to the CRC. To indicate arandom access response that is a response to transmission of a randomaccess preamble of the UE, a random access-RNTI (RA-RNTI) can be maskedto the CRC.

FIG. 8 illustrates an example of an uplink subframe structure.

In FIG. 8, an uplink subframe can be divided into a control region and adata region in a frequency domain. The control region is allocated aphysical uplink control channel (PUCCH) for carrying uplink controlinformation. The data region is allocated a physical uplink sharedchannel (PUSCH) for carrying user data. To maintain a single carrierproperty, one UE does not transmit the PUCCH and the PUSCH at the sametime. The PUCCH for one UE is allocated to an RB pair in a subframe. RBsbelonging to the RB pair each occupy different subcarriers on two slots.This is called that the RB pair allocated to the PUCCH isfrequency-hopped in a slot boundary.

Hereinafter, a frame structure in LTE is described in more detail.

Throughout LTE specification, unless otherwise noted, the size ofvarious fields in the time domain is expressed as a number of time unitsT_(s)=1/(15000×2048) sec.

Downlink and uplink transmissions are organized into radio frames withT_(f)=307200×T_(s)=10 ms duration. Two radio frame structures aresupported.

-   -   Type 1: applicable to FDD    -   Type 2: applicable to TDD

Frame Structure Type 1

Frame structure type 1 is applicable to both full duplex and half duplexFDD. Each radio frame is T_(f)=307200·T_(s)=10 ms long and consists of20 slots of length T_(slot)=15360·T_(s)=0.5 ms, numbered from 0 to 19. Asubframe is defined as two consecutive slots, where subframe i consistsof slots 2i and 2i+1.

For FDD, 10 subframes are available for downlink transmission, and 10subframes are available for uplink transmissions in each 10 ms interval.

Uplink and downlink transmissions are separated in the frequency domain.In half-duplex FDD operation, the UE cannot transmit and receive at thesame time while there are no such restrictions in full-duplex FDD.

FIG. 9 illustrates an example of frame structure type 1.

Frame Structure Type 2

Frame structure type 2 is applicable to TDD. Each radio frame of lengthT_(f)=307200×T_(s)=10 ms consists of two half-frames of length15360·T_(s)=0.5 ms each. Each half-frame consists of five subframes oflength 30720·T_(s)=1 ms. The supported uplink-downlink configurationsare listed in Table 2, where for each subframe in a radio frame, “D”denotes the subframe is reserved for downlink transmissions, “U” denotesthe subframe is reserved for uplink transmissions, and “S” denotes aspecial subframe with the three fields of a downlink pilot time slot(DwPTS), a guard period (GP), and an uplink pilot time slot (UpPTS). Thelength of DwPTS and UpPTS is given by Table 1 subject to the totallength of DwPTS, GP and UpPTS being equal to 30720·T_(s)=1 ms. Eachsubframe i is defined as two slots, 2i and 2i+1 of lengthT_(slot)=15360·T_(s)=0.5 ms in each subframe.

Uplink-downlink configurations with both 5 ms and 10 msdownlink-to-uplink switch-point periodicity are supported. In case of 5ms downlink-to-uplink switch-point periodicity, the special subframeexists in both half-frames. In case of 10 ms downlink-to-uplinkswitch-point periodicity, the special subframe exists in the firsthalf-frame only. Subframes 0 and 5 and DwPTS are always reserved fordownlink transmission. UpPTS and the subframe immediately following thespecial subframe are always reserved for uplink transmission.

FIG. 10 illustrates another example of frame structure type 2.

Table 1 represents an example of configuration of a special subframe.

TABLE 1 normal cyclic extended cyclic prefix in downlink prefix indownlink UpPTS UpPTS normal extended normal extended Special subframecyclic prefix cyclic prefix cyclic prefix cyclic prefix configurationDwPTS in uplink in uplink DwPTS in uplink in uplink 0  6592 · T_(s) 2192· T_(s) 2560 · T_(s)  7680 · T_(s) 2192 · T_(s) 2560 · T_(s) 1 19760 ·T_(s) 20480 · T_(s) 2 21952 · T_(s) 23040 · T_(s) 3 24144 · T_(s) 25600· T_(s) 4 26336 · T_(s)  7680 · T_(s) 4384 · T_(s) 5120 · T_(s) 5  6592· T_(s) 4384 · T_(s) 5120 · T_(s) 20480 · T_(s) 6 19760 · T_(s) 23040 ·T_(s) 7 21952 · T_(s) — — — 8 24144 · T_(s) — — —

Table 2 represents an example of uplink-downlink configuration.

TABLE 2 Downlink-to- Uplink- Uplink- Downlink Switch-point Subframenumber configuration periodicity 0 1 2 3 4 5 6 7 8 9 0 5 ms D S U U U DS U U U 1 5 ms D S U U D D S U U D 2 5 ms D S U D D D S U D D 3 10 ms  DS U U U D D D D D 4 10 ms  D S U U D D D D D D 5 10 ms  D S U D D D D DD D 6 5 ms D S U U U D S U U D

NB-IoT

Narrowband (NB)-Internet of Things (IoT) is the standard for supportinglow complexity and low cost devices and is defined to perform onlyrelatively simple operations as compared to the existing LTE devices.NB-IoT follows a basic structure of the LTE and operates based on thecontents defined below. If NB-IoT reuses channels or signals of LTE,NB-IoT may follow the standard defined in the existing LTE.

Uplink

The following narrowband physical channels are defined.

-   -   Narrowband Physical Uplink Shared Channel (NPUSCH)    -   Narrowband Physical Random Access Channel (NPRACH)

The following uplink narrowband physical signals are defined.

-   -   Narrowband demodulation reference signal

From a subcarrier perspective, an uplink bandwidth N_(sc) ^(UL) and aslot duration T_(slot) are given by the following Table 3.

Table 3 represents an example of NB-IoT parameters.

TABLE 3 Subcarrier spacing NL_(sc) ^(UL) T_(slot) Δf = 3.75 kHz 48 61440· Ts Δf = 15 kHz 12 15360 · Ts

A single antenna port p=0 is used for all the uplink transmissions.

Resource Unit

A resource unit is used to explain mapping of NPUSCH and resourceelements.

The resource unit is defined by consecutive symbols N_(symb)^(UL)N_(slot) ^(UL) in a time domain, and is defined by consecutivesubcarriers N_(sc) ^(UL) in a frequency domain, where N_(sc) ^(UL) andN_(symb) ^(UL) are given by the following Table 4.

Table 4 represents an example of supported combinations of N_(sc) ^(UL),N_(slot) ^(UL) and N_(symb) ^(UL).

TABLE 4 NPUSCH format Δf N_(sc) ^(RU) N_(slots) ^(UL) N_(symb) ^(UL) 13.75 kHz 1 16 7 15 kHz 1 16 3 8 6 4 12 2 2 3.75 kHz 1 4 15 kHz 1 4

Narrowband Physical Uplink Shared Channel (NPUSCH)

A narrowband physical uplink shared channel is supported by two formats.

-   -   NPUSCH format 1 used to carry the UL-SCH    -   NPUSCH format 2 used to carry uplink control information

Scrambling is done according to clause 5.3.1 of TS 36.211. Thescrambling sequence generator is initialized withc_(ini)=n_(RNTI)·2¹⁴+n_(f) mod 2·2¹³+└n_(s)/2┘+N_(ID) ^(cell), wheren_(s) is the first slot of the transmission of the codeword. In case ofNPUSCH repetitions, the scrambling sequence is reinitialized accordingto the above formula after every M_(idendical) ^(NPUSCH) transmission ofthe codeword with n_(s) and n_(f) set to the first slot and the frame,respectively, used for the transmission of the repetition. The quantityM_(idendical) ^(NPUSCH) is given by clause 10.1.3.6 in TS 36.211.

Table 5 specifies the modulation mappings applicable for the narrowbandphysical uplink shared channel.

TABLE 5 Modulation NPUSCH format N_(sc) ^(RU) scheme 1  1 BPSK, QPSK >1QPSK 2  1 BPSK

NPUSCH can be mapped to one or more than one resource units, N_(RU), asgiven by clause of 3GPP TS 36.213, each of which is transmitted M_(rep)^(NPUSCH) times.

The block of complex-valued symbols z(0), . . . , z(M_(rep) ^(NPUSCH)−1)is multiplied with the amplitude scaling factor β_(NPUSCH) in order toconform to the transmit power P_(NPUSCH) specified in 3GPP TS 36.213,and mapped in sequence starting with z(0) to subcarriers assigned fortransmission of NPUSCH. The mapping to resource elements (k, l)corresponding to the subcarriers assigned for transmission and not usedfor transmission of reference signals, is in increasing order of firstthe index k, then the index l, starting with the first slot in theassigned resource unit.

After mapping to N_(slots) slots, the N_(slots) slots are repeatedM_(idendical) ^(NPUSCH)−1 additional times, before continuing themapping of z(·) to the following slot, where the following Equation 1 isrepeated until the slots have been transmitted.

$\begin{matrix}{M_{identical}^{NPUSCH} = \left\{ {{\begin{matrix}{{in}\left( {\left\lceil {M_{rep}^{NPUSCH}/2} \right\rceil,4} \right)} & {N_{sc}^{RU} > 1} \\1 & {N_{sc}^{RU} = 1}\end{matrix}N_{slots}} = \left\{ \begin{matrix}1 & {{\Delta f} = {3.75\mspace{14mu}{kHz}}} \\2 & {{\Delta f} = {15\mspace{14mu}{kHz}}}\end{matrix} \right.} \right.} & \left\lbrack {{Equation}\mspace{14mu} 1} \right\rbrack\end{matrix}$

After transmissions and/or postponements due to NPRACH of 256·30720T_(s)time units, a gap of 40·30720T_(s) time units is inserted where theNPUSCH transmission is postponed. The portion of a postponement due toNPRACH which coincides with a gap is counted as part of the gap.

When higher layer parameter npusch-AllSymbols is set to false, resourceelements in SC-FDMA symbols overlapping with a symbol configured withSRS according to srs-SubframeConfig are counted in the NPUSCH mappingbut not used for transmission of the NPUSCH. When higher layer parameternpusch-AllSymbols is set to true, all symbols are transmitted.

Uplink Control Information on NPUSCH without UL-SCH data

The one bit information of HARQ-ACK o₀ ^(ACK) is coded according toTable 15, where for a positive acknowledgement o₀ ^(ACK)=1 and for anegative acknowledgement o₀ ^(ACK)=0.

Table 6 represents an example of HARQ-ACK code words.

TABLE 6 HARQ-ACK HARQ-ACK <o₀ ^(ACK)> <b₀, b₁, b₂, . . ., b₁₅> 0 <0, 0,0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0> 1 <1, 1, 1, 1, 1, 1, 1, 1, 1,1, 1, 1, 1, 1, 1, 1>

Power Control

The UE transmit power for NPUSCH transmission in NB-IoT UL slot i forthe serving cell is given by the following Equations 2 and 3.

If the number of repetitions of the allocated NPUSCH RUs is greater than2,

P _(NPUSCH,c)(i)=P _(CMAX,c)(i) [dBm]  [Equation 2]

otherwise,

$\begin{matrix}{{P_{{NPUSCH},c}(i)} = {\min\left\{ {\begin{matrix}{{P_{{CMAX},c}(i)},} \\{{10{\log_{10}\left( {M_{{NPUSCH},c}(i)} \right)}} + {P_{{O\_ NPUSCH},c}(j)} + {\alpha_{c}(j)}}\end{matrix} \cdot {PL}_{c}} \right\}{\quad\lbrack{dBm}\rbrack\quad}}} & \left\lbrack {{Equation}\mspace{14mu} 3} \right\rbrack\end{matrix}$

where, P_(CMAX,c)(i) is the configured UE transmit power defined in 3GPPTS 36.101 in NB-IoT UL slot i for serving cell c.

P_(O_NPUSCH)(j) is a parameter composed of the sum of a componentP_(O_NOMIAL_NPUSCH,c)(j) provided from higher layers and a componentP_(O_UE_NPUSCH,c)(j) provided by higher layers for j=1 and for servingcell c, where j∈{1,2}. For NPUSCH (re)transmissions corresponding to adynamic scheduled grant then j=1 and for NPUSCH (re)transmissionscorresponding to the random access response grant then j=2.

P_(O_UE_NPUSCH,c)(2)=0 andP_(O_NORMINAL_NPUSCH,c)(2)=P_(O_PRE)+Δ_(PREAMBLE_Msg3), where theparameter preambleInitialReceivedTargetPower P_(O_PRE) andΔ_(PREAMBLE_Msg3) are signalled from higher layers for serving cell c.

For j=1, for NPUSCH format 2, α_(c)(j)=1; for NPUSCH format 1, α_(c)(j)is provided by higher layers for serving cell c. For j=2, (j)=1.

PL_(c) is the downlink path loss estimate calculated in the UE forserving cell c in dB andPL_(c)=nrs-Power+nrs-PowerOffsetNonAnchor−higher layer filtered NRSRP,where nrs-Power is provided by higher layers and subclause 16.2.2 in3GPP 36.213, nrs-powerOffsetNonAnchor is set to zero if it is notprovided by higher layers and NRSRP is defined in 3GPP TS 36.214 forserving cell c and the higher layer filter configuration is defined in3GPP TS 36.331 for serving cell c.

If the UE transmits NPUSCH in NB-IoT UL slot i for serving cell c, powerheadroom is computed using the following Equation 4.

PH _(c)(i)=P _(CMAX,c)(i)−{P _(O_NPUSCH,c)(1)+α_(c)(1)·PL _(c))}[dB]  [Equation 4]

UE Procedure for Transmitting Format 1 NPUSCH

A UE, upon detection on a given serving cell of a NPDCCH with DCI formatN0 ending in NB-IoT DL subframe n intended for the UE, performs, at theend of n+k₀ DL subframe, a corresponding NPUSCH transmission usingNPUSCH format 1 in N consecutive NB-IoT UL slots n_(i) with i=0, 1, . .. , N−1 according to the NPDCCH information, where

subframe n is the last subframe in which the NPDCCH is transmitted andis determined from the starting subframe of NPDCCH transmission and theDCI subframe repetition number field in the corresponding DCI, and

N=N_(Rep)N_(RU)N_(slots) ^(UL), where the value of N_(Rep) is determinedby the repetition number field in the corresponding DCI, the value ofN_(RU) is determined by the resource assignment field in thecorresponding DCI, and the value of N_(slots) ^(UL) is the number ofNB-IoT UL slots of the resource unit corresponding to the allocatednumber of subcarriers in the corresponding DCI.

n₀ is the first NB-IoT UL slot starting after the end of subframe n+k₀.

The value of k₀ is determined by the scheduling delay field (I_(Delay))in the corresponding DCI according to Table 7.

Table 7 represents an example of k₀ for DCI format N0.

TABLE 7 I_(Delay) k₀ 0  8 1 16 2 32 3 64

The resource allocation information in uplink DCI format N0 for NPUSCHtransmission indicates to a scheduled UE.

-   -   a set of contiguously allocated subcarriers (n_(sc)) of a        resource unit determined by the subcarrier indication field in        the corresponding DCI,    -   a number of resource units (N_(RU)) determined by the resource        assignment field in the corresponding DCI according to Table 9,    -   a repetition number (N_(Rep)) determined by the repetition        number field in the corresponding DCI according to Table 10.

The subcarrier spacing Δf of NPUSCH transmission is determined by theuplink subcarrier spacing field in the narrowband random access responsegrant according to subclause 16.3.3 in 3GPP TS 36.213.

For NPUSCH transmission with subcarrier spacing Δf=3.75 kHz,n_(sc)=I_(SC), where I_(SC) is the subcarrier indication field in theDCI.

For NPUSCH transmission with subcarrier spacing Δf=15 kHz, thesubcarrier indication field (I_(SC)) in the DCI determines the set ofcontiguously allocated subcarriers (n_(sc)) according to Table 8.

Table 8 represents an example of allocated subcarriers for NPUSCH withΔf=15 kHz.

TABLE 8 Subcarrier indication field (I_(sc)) Set of Allocatedsubcarriers (n_(sc))  0-11 I_(sc) 12-15 3 (I_(sc)-12) + {0, 1, 2} 16-176 (I_(sc)-16) + {0, 1, 2, 3, 4, 5} 18 {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10,11} 19-63 Reserved

Table 9 represents an example of the number of resource units forNPUSCH.

TABLE 9 I_(RU) N_(RU) 0 1 1 2 2 3 3 4 4 5 5 6 6 8 7 10

Table 10 represents an example of the number of repetitions for NPUSCH.

TABLE 10 I_(Rep) N_(Rep) 0 1 1 2 2 4 3 8 4 16 5 32 6 64 7 128

Demodulation Reference Signal (DMRS)

The reference signal sequence r _(u)(n) for N_(sc) ^(RU)=1 is defined bythe following Equation 1.

$\begin{matrix}{{{\overset{\_}{r}}_{u} = {\frac{1}{\sqrt{2}}\left( {1 + j} \right)\left( {1 - {2{c(n)}}} \right){w\left( {n\mspace{14mu}{mod}\mspace{14mu} 16} \right)}}},{0 \leq n < {M_{rep}^{NPUSCH}N_{RU}N_{slots}^{UL}}}} & \left\lbrack {{Equation}\mspace{14mu} 5} \right\rbrack\end{matrix}$

where the binary sequence c(n) is defined by clause 7.2 of TS 36.211 andshall be initialized with c_(init)=35 at the start of the NPUSCHtransmission. The quantity w(n) is given by Table 11 where u=N_(ID)^(Ncell) mod 16 for NPUSCH format 2, and for NPUSCH format 1 if grouphopping is not enabled, and by clause 10.1.4.1.3 of 3GPP TS 36.211 ifgroup hopping is enabled for NPUSCH format 1.

Table 11 represents an example of w(n).

TABLE 11 u w(0), . . . , w(15)  0 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1  1 1−1 1 −1 1 −1 1 −1 1 −1 1 −1 1 −1 1 −1  2 1 1 −1 −1 1 1 −1 −1 1 1 −1 −1 11 −1 −1  3 1 −1 −1 1 1 −1 −1 1 1 −1 −1 1 1 −1 −1 1  4 1 1 1 1 −1 −1 −1−1 1 1 1 1 −1 −1 −1 −1  5 1 −1 1 −1 −1 1 −1 1 1 −1 1 −1 −1 1 −1 1  6 1 1−1 −1 −1 −1 1 1 1 1 −1 −1 −1 −1 1 1  7 1 −1 −1 1 −1 1 1 −1 1 −1 −1 1 −11 1 −1  8 1 1 1 1 1 1 1 1 −1 −1 −1 −1 −1 −1 −1 −1  9 1 −1 1 −1 1 −1 1 −1−1 1 −1 1 −1 1 −1 1 10 1 1 −1 −1 1 1 −1 −1 −1 −1 1 1 −1 −1 1 1 11 1 −1−1 1 1 −1 −1 1 −1 1 1 −1 −1 1 1 −1 12 1 1 1 1 −1 −1 −1 −1 −1 −1 −1 −1 11 1 1 13 1 −1 1 −1 −1 1 −1 1 −1 1 −1 1 1 −1 1 −1 14 1 1 −1 −1 −1 −1 1 1−1 −1 1 1 1 1 −1 −1 15 1 −1 −1 1 −1 1 1 −1 −1 1 1 −1 1 −1 −1 1

The reference signal sequence for NPUSCH format 1 is given by thefollowing Equation 6.

r _(u)(n)= r _(u)(n)  [Equation 6]

The reference signal sequence for NPUSCH format 2 is given by thefollowing Equation 7.

r _(u)(3n+m)= w (m) r _(u)(n),m=0,1,2  [Equation 7]

where w(m) is defined in Table 5.5.2.2.1-2 of 3GPP TS 36.211 with thesequence index chosen according to

$\left( {\sum\limits_{i = 0}^{7}{{c\left( {{8n_{s}} + i} \right)}2^{i}}} \right){mod}\mspace{14mu} 3$

with c_(init)=N_(ID) ^(Ncell.)

The reference signal sequences r_(u)(n) for N_(sc) ^(RU)>1 is defined bya cyclic shift α of a base sequence according to the following Equation8.

$\begin{matrix}{\mspace{79mu}{{{{r_{u}(n)} = {\text{?}e^{j\;{\phi{(n)}}{\pi/4}}}},{0 \leq n < N_{sc}^{RU}}}{\text{?}\text{indicates text missing or illegible when filed}}}} & \left\lbrack {{Equation}\mspace{14mu} 8} \right\rbrack\end{matrix}$

where φ(n) is given by Table 21 for N_(sc) ^(RU)=3, and Table 22 forN_(sc) ^(RU)=6.

If group hopping is not enabled, the base sequence index u is given byhigher layer parameters threeTone-BaseSequence, sixTone-BaseSequence,and twelveTone-BaseSequence for N_(sc)=3, N_(sc) ^(RU)=6, and N_(sc)^(RU)=12, respectively. If not signalled by higher layers, the basesequence is given by the following Equation 9.

$\begin{matrix}{u = \left\{ \begin{matrix}{N_{ID}^{Ncell}{mod12}} & {{{for}\mspace{14mu} N_{sc}^{RU}} = 3} \\{N_{ID}^{Ncell}{mod14}} & {{{for}\mspace{14mu} N_{sc}^{RU}} = 6} \\{N_{ID}^{Ncell}{mod30}} & {{{for}\mspace{14mu} N_{sc}^{RU}} = 12}\end{matrix} \right.} & \left\lbrack {{Equation}\mspace{14mu} 9} \right\rbrack\end{matrix}$

If group hopping is enabled, the base sequence index u is given byclause 10.1.4.1.3 of 3GPP TS 36.211.

The cyclic shift for N_(sc) ^(RU)=3 and N_(sc) ^(RU)=6 is derived fromhigher layer parameters threeTone-CyclicShift and sixTone-CyclicShift,respectively, as defined in Table 23. For N_(sc) ^(RU)=12, α=0.

Table 12 represents an example of φ(n) for N_(sc) ^(RU)=3.

TABLE 12 u φ(0), φ(1), φ(2)  0 1 −3 −3  1 1 −3 −1  2 1 −3 3  3 1 −1 −1 4 1 −1 1  5 1 −1 3  6 1 1 −3  7 1 1 −1  8 1 1 3  9 1 3 −1 10 1 3 1 11 13 3

Table 13 represents another example of φ(n) for N_(sc) ^(RU)=6.

TABLE 13 u φ(0), . . . , φ(5)  0 1 1 1 1 3 −3  1 1 1 3 1 −3 3  2 1 −1 −1−1 1 −3  3 1 −1 3 −3 −1 −1  4 1 3 1 −1 −1 3  5 1 −3 −3 1 3 1  6 −1 −1 1−3 −3 −1  7 −1 −1 −1 3 −3 −1  8 3 −1 1 −3 −3 3  9 3 −1 3 −3 −1 1 10 3 −33 −1 3 3 11 −3 1 3 1 −3 −1 12 −3 1 −3 3 −3 −1 13 −3 3 −3 1 1 −3

Table 14 represents an example of α.

TABLE 14 N_(sc) ^(RU) = 3 N_(sc) ^(RU) = 6 threeTone-CyclicShift αsixTone-CyclicShift α 0 0 0 0 1 2π/3 1 2π/6 2 4π/3 2 4π/6 3 8π/6

For the reference signal for NPUSCH format 1, sequence-group hopping canbe enabled, where the sequence-group number u in slot n_(s) is definedby a group hopping pattern f_(gh)(n_(s)) and a sequence-shift patternf_(ss) according to the following Equation 10.

u=(f _(gh)(n _(s))+f _(ss))mod N _(seq) ^(RU)  [Equation 10]

where the number of reference signal sequences available for eachresource unit size, N_(seq) ^(RU) is given by the following Table 15.

TABLE 15 N_(sc) ^(RU) N_(seq) ^(RU)  1 16  3 12  6 14 12 30

Sequence-group hopping can be enabled or disabled by means of thecell-specific parameter groupHoppingEnabled provided by higher layers.Sequence-group hopping for NPUSCH can be disabled for a certain UEthrough the higher-layer parameter groupHoppingDisabled despite beingenabled on a cell basis unless the NPUSCH transmission corresponds to arandom access response grant or a retransmission of the same transportblock as part of the contention based random access procedure.

The group hopping pattern f_(gh)(n_(s)) is given by the followingEquation 11.

$\begin{matrix}{\mspace{79mu}{{{f_{gh}\left( \text{?} \right)} = {\left( {\text{?}{{c\left( {{8n_{s}^{\prime}} + i} \right)} \cdot 2^{i}}} \right){{mod}N}_{seq}^{RU}}}{\text{?}\text{indicates text missing or illegible when filed}}}} & \left\lbrack {{Equation}\mspace{14mu} 11} \right\rbrack\end{matrix}$

where n′_(s)=n_(s) for N_(sc) ^(RU)>1 and n′_(s) is the slot number ofthe first slot of the resource unit for N_(sc) ^(RU)>1. Thepseudo-random sequence c(i) is defined by clause 7.2. The pseudo-randomsequence generator is initialized with

$c_{init} = \left\lfloor \frac{N_{ID}^{Ncell}}{N_{seq}^{RU}} \right\rfloor$

at the beginning of the resource unit for N_(sc) ^(RU)=1 and in everyeven slot for N_(sc) ^(RU)>1.

The sequence-shift pattern fs, is given by the following Equation 12.

f _(ss)=(N _(ID) ^(Ncell)+Δ_(ss))mod N _(seq) ^(RU)  [Equation 12]

where Δ_(ss)∈{0, 1, . . . , 29} is given by higher-layer parametergroupAssignmentNPUSCH. If no value is signalled, Δ_(ss)=0.

The sequence r(⋅) shall be multiplied with the amplitude scaling factorβ_(NPUSCH) and mapped in sequence starting with r(0) to thesub-carriers.

The set of subcarriers used in the mapping process shall be identical tothe corresponding NPUSCH transmission as defined in clause 10.1.3.6 in3GPP 36.211.

The mapping to resource elements (k, l) shall be in increasing order offirst k, then l, and finally the slot number. The values of the symbolindex l in a slot are given in Table 25.

Table 16 represents an example of the demodulation reference signallocation for NPUSCH.

TABLE 16 Values for l NPUSCH format Δf = 3.75 kHz Δf = 15 kHz 1 4 3 2 0,1, 2 2, 3, 4

SF-FDMA Baseband Signal Generation

For N_(sc) ^(RU)>1, the time-continuous signal s_(l)(t) in SC-FDMAsymbol l in a slot is defined by clause 5.6 with the quantity N_(RB)^(UL) N_(sc) ^(RB replaced by N) _(sc) ^(UL).

For N_(sc) ^(RU)=1, the time-continuous signal s_(k,l)(t) forsub-carrier index k in SC-FDMA symbol l in an uplink slot is defined byEquation 13.

s _(k,l)(t)=a _(k) ⁽⁻⁾ _(,l) ·e ^(jϕ) ^(k,l) ·e ^(j2π(k+1/2)Δf(t−N)^(CP,l) ^(T) ^(s) ⁾

k ⁽⁻⁾ =k+└N _(sc) ^(UL)/2┘  [Equation 13]

For 0≤t<(N_(CP,l)+N)T_(s) where parameters for Δf=15 kHz and Δf=3.75 kHzare given in Table 26, a_(k) ⁽⁻⁾ _(,l) is the modulation value of symboll and the phase rotation φ_(k,l) is defined by Equation 14.

$\begin{matrix}{\mspace{79mu}{{\varphi_{k,l} = {{\rho\left( {\overset{\sim}{l}\mspace{14mu}{mod2}} \right)} + {{\hat{\varphi}}_{k}\left( \overset{\sim}{l} \right)}}}\mspace{20mu}{\rho = \left\{ {{\begin{matrix}\frac{\pi}{2} & {{for}\mspace{14mu}{BPSK}} \\\frac{\pi}{4} & {{for}\mspace{14mu}{QPSK}}\end{matrix}{{\hat{\varphi}}_{k}\left( \overset{\sim}{l} \right)}} = \left\{ {{{\begin{matrix}0 & {\overset{\sim}{l} = 0} \\{{{\overset{\sim}{\varphi}}_{k}\left( {\overset{\sim}{l} - 1} \right)} + {2{{{\pi\Delta}f}\left( {k + {1/2}} \right)}\left( {N + N_{{CP},l}} \right)T_{s}}} & {\overset{\sim}{i} > 0}\end{matrix}\mspace{20mu}\overset{\sim}{l}} = 0},1,\ldots,{{{M_{rep}^{NPUSCH}N_{RU}N_{slots}^{UL}N_{symb}^{UL}} - {1\mspace{20mu} l}} = {\overset{\sim}{l}\mspace{14mu}{mod}\mspace{14mu} N_{symb}^{UL}}}} \right.} \right.}}} & \left\lbrack {{Equation}\mspace{14mu} 14} \right\rbrack\end{matrix}$

where {tilde over (l)} is a symbol counter that is reset at the start ofa transmission and incremented for each symbol during the transmission.

Table 17 represents an example of SC-FDMA parameters for N_(sc) ^(RU)=1.

TABLE 17 Parameter Δf = 3.75 kHz Δf = 15 kHz N 8192 2048 Cyclic prefixlength 256 160 for l = 0 N_(CP, l) 144 for l = 1,2, . . ., 6 Set ofvalues for k −24, −23, . . ., 23 −6, −5, . . ., 5

The SC-FDMA symbols in a slot shall be transmitted in increasing orderof l, starting with l=0, where SC-FDMA symbol l>0 starts at timeΣ_(l′=0) ^(l−1)(N_(CP,l′)+N)T_(s) within the slot. For Δf=3.75 kHz, theremaining 2304T_(s) in T_(slot) is not transmitted and used for guardperiod.

Narrowband Physical Random Access Channel (NPRACH)

The physical layer random access preamble is based on single-subcarrierfrequency-hopping symbol groups. A symbol group is a random accesssymbol group illustrated in FIG. 11, consisting of a cyclic prefix oflength T_(CP) and a sequence of 5 identical symbols with total lengthT_(SEQ). The parameter values are random access preamble parameterslisted in Table 27.

FIG. 11 illustrates an example of the random access symbol group.

Table 18 represents an example of the random access preamble parameters.

TABLE 18 Preamble format T_(CP) T_(SEQ) 0 2048T_(s) 5 · 8192T_(s) 18192T_(s) 5 · 8192T_(s)

The preamble consisting of 4 symbol groups transmitted without gaps istransmitted N_(rep) ^(NPRACH) times.

The transmission of a random access preamble, if triggered by the MAClayer, is restricted to certain time and frequency resources.

A NPRACH configuration provided by higher layers contains the following.

NPRACH resource periodicity N_(period) ^(NPRACH) (nprach-Periodicity),

Frequency location of the first subcarrier allocated to NPRACHN_(scoffset) ^(NPRACH) (nprach-SubcarrierOffset),

The number of subcarriers allocated to NPRACH N_(sc) ^(NPRACH)(nprach-NumSubcarriers),

The number of starting subcarriers allocated to contention based NPRACHrandom access N_(sc_cont) ^(NPRACH) (nprach-NumCBRA-StartSubcarriers),

The number of NPRACH repetitions per attempt N_(rep) ^(NPRACH)(numRepetitionsPerPreambleAttempt),

NPRACH starting time N_(start) ^(NPRACH) (nprach-StartTime),

Fraction for calculating starting subcarrier index for the range ofNPRACH subcarriers reserved for indication of UE support for multi-tonemsg3 transmission N_(MSG3) ^(NPRACH) (nprach-SubcarrierMSG3-RangeStart).

NPRACH transmission can start only N_(start) ^(NPRACH)·30720 T_(s) timeunits after the start of a radio frame fulfilling n_(f) mod(N_(period)^(NPRACH)/10)=0. After transmissions of 4·64 (T_(CP)+T_(SEQ))time units,a gap of 40·30720T_(s) time units is inserted.

NPRACH configurations where N_(scoffset) ^(NPRACH)+N_(sc)^(NPRACH)>N_(sc) ^(UL) are invalid.

The NPRACH starting subcarriers allocated to contention based randomaccess are split in two sets of subcarriers, {0, 1, . . . , N_(sc)_(cont) ^(NPRACH)N_(MSG3) ^(NPRACH)−1} and {N_(sc_cont)^(NPRACH)N_(MSG3) ^(NPRACH), . . . , N_(sc) _(cont) ^(NPRACH)−1}, wherethe second set, if present, indicates UE support for multi-tone msg3transmission.

The frequency location of the NPRACH transmission is constrained withinN_(sc) ^(RA)=12 subcarriers. Frequency hopping is used within the 12subcarriers, where the frequency location of the i^(th) symbol group isgiven by n_(sc) ^(RA)(i)=n_(start)+ñ_(sc) ^(RA)(i) wheren_(start)=N_(scoffset) ^(NPRACH)+└n_(init)/N_(sc) ^(RA)┘·N_(sc) ^(RA),and

$\begin{matrix}{{{\overset{\sim}{n}}_{sc}^{RA}(i)} = \left\{ {{\begin{matrix}{\left( {{{\overset{\sim}{n}}_{sc}^{RA}(0)} + {f\left( {i/4} \right)}} \right){mod}\mspace{14mu} N_{sc}^{RA}} & {{i\mspace{14mu}{mod4}} = {{0\mspace{14mu}{and}\mspace{14mu} i} > 0}} \\{{{\overset{\sim}{n}}_{sc}^{RA}\left( {i - 1} \right)} + 1} & {{{i\mspace{14mu}{mod4}} = 1},{{3\mspace{14mu}{and}\mspace{14mu}{{\overset{\sim}{n}}_{sc}^{RA}\left( {i - 1} \right)}{mod2}} = 0}} \\{{{\overset{\sim}{n}}_{sc}^{RA}\left( {i - 1} \right)} - 1} & {{{i\mspace{14mu}{mod4}} = 1},{{3\mspace{14mu}{and}\mspace{14mu}{{\overset{\sim}{n}}_{sc}^{RA}\left( {i - 1} \right)}{mod2}} = 1}} \\{{{\overset{\sim}{n}}_{sc}^{RA}\left( {i - 1} \right)} + 6} & {{i\mspace{14mu}{mod4}} = {{2\mspace{14mu}{and}\mspace{14mu}{{\overset{\sim}{n}}_{sc}^{RA}\left( {i - 1} \right)}} < 6}} \\{{{\overset{\sim}{n}}_{sc}^{RA}\left( {i - 1} \right)} - 6} & {{i\mspace{14mu}{mod4}} = {{2\mspace{14mu}{and}\mspace{14mu}{{\overset{\sim}{n}}_{sc}^{RA}\left( {i - 1} \right)}} \geq 6}}\end{matrix}{f(t)}} = {{\left( {{f\left( {t - 1} \right)} + {\left( {\sum\limits_{n = {{10t} + 1}}^{{10t} + 0}{{c(n)}2^{n - {({{10t} + 1})}}}} \right){{mod}\left( {N_{sc}^{RA} - 1} \right)}} + 1} \right){mod}\mspace{14mu} N_{sc}^{RA}{f\left( {- 1} \right)}} = 0}} \right.} & \left\lbrack {{Equation}\mspace{14mu} 15} \right\rbrack\end{matrix}$

where ñ_(SC) ^(RA)(0)=n_(init) mod N_(sc) ^(RA) with n_(init) being thesubcarrier selected by the MAC layer from {0, 1, . . . , N_(sc)^(NPRACH)−1}, and the pseudo random sequence c(n) is given by clause 7.2of 3GPP TS36.211. The pseudo random sequence generator is initializedwith c_(init)=N_(ID) ^(Ncell).

The time-continuous random access signal s_(i)(t) for symbol group i isdefined by the following Equation 16.

s _(i)(t)=β_(NPRACH) ^(j2π(n) ^(SC) ^(RA) ^((i)+Kk) ^(ij) ^(+1/2)Δf)^(RA) ^((t−T) ^(CP) ⁾  [Equation 16]

Where 0≤t<T_(SEQ)+T_(CP), β_(NPRACH) is an amplitude scaling factor inorder to conform to the transmit power P NPRACH specified in clause16.3.1 in 3GPP TS 36.213, k₀=−N_(sc) ^(UL)/2, K=Δf/Δf_(RA) accounts forthe difference in subcarrier spacing between the random access preambleand uplink data transmission, and the location in the frequency domaincontrolled by the parameter n_(sc) ^(RA) (i) is derived from clause10.1.6.1 of 3GPP TS 36.211. The variable Δf_(RA) is given by Table 28.

Table 19 represents an example of random access baseband parameters.

TABLE 19 Preamble format Δf_(RA) 0, 1 3.75 kHz

Downlink

A downlink narrowband physical channel corresponds to a set of resourceelements carrying information originating from higher layers and is theinterface defined between 3GPP TS 36.212 and 3GPP TS 36.211.

The following downlink physical channels are defined:

-   -   Narrowband Physical Downlink Shared Channel (NPDSCH)    -   Narrowband Physical Broadcast Channel (NPBCH)    -   Narrowband Physical Downlink Control Channel (NPDCCH)

A downlink narrowband physical signal corresponds to a set of resourceelements used by the physical layer but does not carry informationoriginating from higher layers.

A downlink narrowband physical signal corresponds to a set of resourceelements used by the physical layer but does not carry informationoriginating from higher layers. The following downlink physical signalsare defined:

-   -   Narrowband reference signal (NRS)    -   Narrowband synchronization signal    -   Narrowband physical downlink shared channel (NPDSCH)

The scrambling sequence generator is initialized withc_(ini)=n_(RNTI)·2¹⁴+n_(f) mod 2·2¹³+└n_(s)/2┘+N_(ID) ^(Ncell), wheren_(s) is the first slot of the transmission of the codeword. In case ofNPDSCH repetitions and the NPDSCH carrying the BCCH, the scramblingsequence generator is reinitialized according to the expression abovefor each repetition. In case of NPDSCH repetitions and the NPDSCH is notcarrying the BCCH, the scrambling sequence generator is reinitializedaccording to the expression above after every min (M_(rep) ^(NPDSCH),4)transmission of the codeword with n_(s) and n_(f) set to the first slotand the frame, respectively, used for the transmission of therepetition.

Modulation is done using a QPSK modulation scheme.

NPDSCH can be mapped to one or more than one subframes, N_(SF), as givenby N_(rep) ^(NPDSCH) clause 16.4.1.5 of 3GPP TS 36.213, each of whichshall be transmitted NPDSCH M_(rep) ^(NPDSCH) times.

For each of the antenna ports used for transmission of the physicalchannel, the block of complex-valued symbols y^((p))(0), . . . y^((p))(M_(symb) ^(ap)−1) shall be mapped to resource elements (k, l) whichmeet all of the following criteria in the current subframe.

The subframe is not used for transmission of NPBCH, NPSS, or NSSS, and

they are assumed by the UE not to be used for NRS, and

they are not overlapping with resource elements used for CRS (if any),and

the index l in the first slot in a subframe fulfils l≥l_(DataStart)where l_(DataStart) is given by clause 16.4.1.4 of 3GPP TS 36.213.

The mapping of y^((p))(0), . . . y^((p)) (M_(symb) ^(ap)−1) in sequencestarting with y^((p))(0) to resource elements (k, l) on antenna port pmeeting the criteria above is increasing order of the first the index kand the index l, starting with the first slot and ending with the secondslot in a subframe. For NPDSCH not carrying BCCH, after mapping to asubframe, the subframe is repeated for M_(rep) ^(NPDSCH)−1 additionalsubframes, before continuing the mapping of y^((p))(⋅) to the followingsubframe. The mapping of y^((p))(0), . . . y^((p))(M_(symb) ^(ap)−1) isthen repeated until M_(rep) ^(NPDSCH)N_(SF) subframes have beentransmitted. For NPDSCH carrying BCCH, the y^((p))(0), . . .y^((p))(M_(symb) ^(ap)−1) is mapped to N_(SF) subframes in sequence andthen repeated until M_(rep) ^(NPDSCH)N_(SF) subframes have beentransmitted.

The NPDSCH transmission can be configured by higher layers withtransmission gaps where the NPSDCH transmission is postponed. There areno gaps in the NPDSCH transmission if R_(max)<N_(gap,threshold) whereN_(gap,threshold) is given by the higher layer parameter dl-GapThresholdand R_(max) is given by 3GPP TS 36.213. The gap starting frame andsubframe are given by (10n_(f)+└n_(s)/2┘) mod N_(gap,period)=0 where thegap periodicity, N_(gap,period) is given by the higher layer parameterdl-GapPeriodicity. The gap duration in a plurality of subframes is givenby N_(gap,duration)=N_(gap,coeff)N_(gap,period), where N_(gap,coeff) isgiven by the higher layer parameter dl-GapDurationCoeff. For NPDSCHcarrying the BCCH there are no gaps in the transmission.

The UE does not expect NPDSCH in subframe i if it is not a NB-IoTdownlink subframe, except for transmissions of NPDSCH carryingSystemInformationBlockType1-NB in subframe 4. In case of NPDSCHtransmissions, in subframes that are not NB-IoT downlink subframes, theNPDSCH transmission is postponed until the next NB-IoT downlinksubframe.

UE Procedure for Receiving the NPDSCH

A NB-IoT UE shall assume a subframe as a NB-IoT DL subframe in thefollowing case.

-   -   If the UE determines that the subframe does not contain        NPSS/NSSS/NPBCH/NB-SIB1 transmission, and    -   for a NB-IoT carrier that a UE receives higher layer parameter        operationModeInfo, the subframe is configured as NB-IoT DL        subframe after the UE has obtained        SystemInformationBlockType1-NB.    -   for a NB-IoT carrier that DL-CarrierConfigCommon-NB is present,        the subframe is configured as NB-IoT DL subframe by the higher        layer parameter downlinkBitmapNonAnchor.

For a NB-IoT UE that supports twoHARQ-Processes-r14, there shall be amaximum of 2 downlink HARQ processes.

A UE shall upon detection on a given serving cell of a NPDCCH with DCIformat N1, N2 ending in subframe n intended for the UE, decode, startingin n+5 DL subframe, the corresponding NPDSCH transmission in Nconsecutive NB-IoT DL subframe(s) n_(i) with i=0, 1, . . . , N−1according to the NPDCCH information, where

subframe n is the last subframe in which the NPDCCH is transmitted andis determined from the starting subframe of NPDCCH transmission and theDCI subframe repetition number field in the corresponding DCI.

subframe(s) n_(i) with i=0, 1, . . . , N−1 are N consecutive NB-IoT DLsubframe(s) excluding subframes used for SI messages, where n₀<n₁< . . ., n_(N−1),

N=N_(Rep)N_(SF), where the value of N_(Rep) is determined by therepetition number field in the corresponding DCI, and the value ofN_(SF) is determined by the resource assignment field in thecorresponding DCI, and

k₀ is the number of NB-IoT DL subframe(s) starting in DL subframe n+5until DL subframe n₀, where k₀ is determined by the scheduling delayfield (I_(Delay)) for DCI format N1, and k₀=0 for DCI format N2. For DCICRC scrambled by G-RNTI, k₀ is determined by the scheduling delay field(I_(Delay)) according to Table 30, otherwise k₀ is determined by thescheduling delay field (I_(Delay)) according to Table 29. The value ofR_(max) is according to subclause 16.6 in 3GPP 36.213 for thecorresponding DCI format N1.

Table 20 represents an example of k₀ for DCI format N1.

TABLE 20 k₀ I_(Delay) R_(max) < 128 R_(max) ≥ 128 0 0 0 1 4 16 2 8 32 312 64 4 16 128 5 32 256 6 64 512 7 128 1024

Table 21 represents an example of k₀ for DCI format N1 with DCI CRCscrambled by G-RNTI.

TABLE 21 I_(Delay) k₀ 0 0 1 4 2 8 3 12 4 16 5 32 6 64 7 128

A UE is not expected to receive transmissions in 3 DL subframesfollowing the end of a NPUSCH transmission by the UE.

The resource allocation information in DCI format N1, N2 (paging) forNPSICH indicates the following information to a scheduled UE.

-   -   a number of subframes (N_(SF)) determined by the resource        assignment field (I_(SF)) in the corresponding DCI according to        Table 22,    -   a repetition number (N_(Rep)) determined by the repetition        number field (I_(Rep)) in the corresponding DCI according to        Table 23.

TABLE 22 I_(SF) N_(SF) 0 1 1 2 2 3 3 4 4 5 5 6 6 8 7 10

TABLE 23 I_(Rep) N_(Rep)  0 1  1 2  2 4  3 8  4 16  5 32  6 64  7 128  8192  9 256 10 384 11 512 12 768 13 1024 14 1536 15 2048

The number of repetitions for the NPDSCH carryingSystemInformationBlockType1-NB is determined based on the parameterschedulingInfoSIB1 configured by higher-layers and according to Table33.

Table 24 represents an example of number of repetitions for SIB1-NB.

TABLE 24 Value of scheduling Info SIB1 Number of NPDSCH repetitions  0 4 1 8  2 16  3 4  4 8  5 16  6 4  7 8  8 16  9 4 10 8 11 16 12-15Reserved

The starting radio frame for the first transmission of the NPDSCHcarrying SystemInformationBlockType1-NB is determined according to Table25.

Table 25 represents an example of the starting radio frame for the firsttransmission of the NPDSCH carrying SIB1-NB.

TABLE 25 Starting radio Number of frame number NPDSCH for NB-SIBIrepetitions N_(ID) ^(Ncell) repetitions (nf mod 256)  4 N_(ID) ^(Ncell)mod 4 = 0 0 N_(ID) ^(Ncell) mod 4 = 1 16 N_(ID) ^(Ncell) mod 4 = 2 32N_(ID) ^(Ncell) mod 4 = 3 48  8 N_(ID) ^(Ncell) mod 2 = 0 0 N_(ID)^(Ncell) mod 2 = 1 16 16 N_(ID) ^(Ncell) mod 2 = 0 0 N_(ID) ^(Ncell) mod2 = 1 1

The starting OFDM symbol for NPDSCH is given by index l_(DataStrart) inthe first slot in a subframe k and is determined as follows.

-   -   If subframe k is a subframe used for receiving SIB1-NB,

l_(DataStrart)=3 if the value of the high layer parameteroperationModeInfo is set to ‘00’ or ‘01’,

l_(DataStrart)=0 otherwise

-   -   else,

l_(DataStrart) is given by the higher layer parametereutraControlRegionSize if the value of the higher layer parametereutraControlRegionSize is present

l_(DataStrart)=0 otherwise.

UE Procedure for Reporting ACK/NACK

The UE shall upon detection of a NPDSCH transmission ending in NB-IoTsubframe n intended for the UE and for which an ACK/NACK shall beprovided, start, at the end of n+k₀−1 DL subframe transmission of theNPUSCH carrying ACK/NACK response using NPUSCH format 2 in N consecutiveNB-IoT UL slots, where N=N_(Rep) ^(AN)N_(slots) ^(UL), where the valueof N_(Rep) ^(AN) is given by the higher layer parameterack-NACK-NumRepetitions-Msg4 configured for the associated NPRACHresource for Msg4 NPDSCH transmission, and higher layer parameterack-NACK-NumRepetitions otherwise, and the value of N_(slots) ^(UL) isthe number of slots of the resource unit,

allocated subcarrier for ACK/NACK and value of k0 is determined by theACK/NACK resource field in the DCI format of the corresponding NPDCCHaccording to Table 16.4.2-1, and Table 16.4.2-2 in 3GPP TS 36.213.

Narrowband Physical Broadcast Channel (NPBCH)

The processing structure for the BCH transport channel is according tosection 5.3.1 of 3GPP TS 36.212, with the following differences.

-   -   The transmission time interval (TTI) is 640 ms.    -   The size of the BCH transport block is set to 34 bits.    -   The CRC mask for NPBCH is selected according to 1 or 2 transmit        antenna ports at eNodeB according to Table 5.3.1.1-1 of 3GPP TS        36.212, where the transmit antenna ports are defined in section        10.2.6 of 3GPP TS 36.211.    -   The number of rate matched bits is defined in section 10.2.4.1        of 3GPP TS 36.211.

Scrambling is done according to clause 6.6.1 of 3GPP TS 36.211 withM_(bit) denoting the number of bits to be transmitted on the NPBCH.M_(bit) equals 1600 for normal cyclic prefix. The scrambling sequence isinitialized with c_(init)=N_(ID) ^(Ncell) in radio frames fulfillingn_(f) mod 64=0.

Modulation is done using the QPSK modulation scheme for each antennaport and is transmitted in subframe 0 during 64 consecutive radio framesstarting in each radio frame fulfilling n_(f) mod 64=0.

Layer mapping and precoding are done according to clause 6.6.3 of 3GPPTS 36.211 with P∈{1,2}. The UE assumes antenna ports R₂₀₀₀ and R₂₀₀₁ areused for the transmission of the narrowband physical broadcast channel.

The block of complex-valued symbols y^((p))(0), . . .y^((p))(M_(symb)−1) for each antenna port is transmitted in subframe 0during 64 consecutive radio frames starting in each radio framefulfilling n_(f) mod 64=0 and shall be mapped in sequence startingconsecutive radio frames starting with y(0) to resource elements (k, l)not reserved for transmission of reference signals shall be inincreasing order of the first the index k, then the index l. Aftermapping to a subframe, the subframe is repeated in subframe 0 in the 7following radio frames, before continuing the mapping of y^((p))(⋅) tosubframe 0 in the following radio frame. The first three OFDM symbols ina subframe are not used in the mapping process. For the purpose of themapping, the UE assumes cell-specific reference signals for antennaports 0-3 and narrowband reference signals for antenna ports 2000 and2001 being present irrespective of the actual configuration. Thefrequency shift of the cell-specific reference signals is calculated byreplacing cell N_(ID) ^(cell) with N_(ID) ^(cell) in the calculation ofv_(shift) in clause 6.10.1.2 of 3GPP TS 36.211.

Narrowband Physical Downlink Control Channel (NPDCCH)

The narrowband physical downlink control channel carries controlinformation. A narrowband physical control channel is transmitted on anaggregation of one or two consecutive narrowband control channelelements (NCCEs), where a narrowband control channel element correspondsto 6 consecutive subcarriers in a subframe where NCCE 0 occupiessubcarriers 0 through 5 and NCCE 1 occupies subcarriers 6 through 11.The NPDCCH supports multiple formats as listed in Table 35. For NPDCCHformat 1, all NCCEs belong to the same subframe. One or two NPDCCHs canbe transmitted in a subframe.

Table 26 represents an example of supported NPDCCH formats.

TABLE 26 NPDCCH Format Number of NCCEs 0 1 1 2

Scrambling shall be done according to clause 6.8.2 of TS 36.211. Thescrambling sequence shall be initialized at the start of subframe k₀according to section 16.6 of TS 36.213 after every 4th NPDCCH subframewith c_(init)=└n_(s)/2┘2⁹+N_(ID) ^(cell), where n_(s) is the first slotof the NPDCCH subframe in which scrambling is (re-)initialized.

Modulation is done according to clause 6.8.3 of TS 36.211 using the QPSKmodulation scheme.

Layer mapping and precoding are done according to clause 6.6.3 of TS36.211 using the same antenna ports as the NPBCH.

The block of complex-valued symbols y(0), . . . y(M_(symb)−1) is mappedin sequence starting with y(0) to resource elements (k, l) on theassociated antenna port which meets all of the following criteria.

They are part of the NCCE(s) assigned for the NPDCCH transmission, and

they are assumed not to be used for transmission of NPBCH, NPSS, orNSSS, and

they are assumed by the UE not to be used for NRS, and

they are not overlapping with resource elements used for PBCH, PSS, SSS,or CRS as defined in clause 6 of TS 36.211 (if any), and

the index l in the first slot in a subframe fulfils l≥l_(NPDCCHStart),where l_(NPDCCHStart) is given by clause 16.6.1 of 3GPP TS 36.213.

The mapping to resource elements (k, l) on antenna port p meeting thecriteria above is in increasing order of first the index k and then theindex l, starting with the first slot and ending with the second slot ina subframe.

The NPDCCH transmission can be configured by higher layers withtransmissions gaps where the NPDCCH transmission is postponed. Theconfiguration is the same as described for NPDSCH in clause 10.2.3.4 ofTS 36.211.

The UE does not expect NPDCCH in subframe i if it is not a NB-IoTdownlink subframe. In case of NPDCCH transmissions, in subframes thatare not NB-IoT downlink subframes, the NPDCCH transmissions arepostponed until the next NB-IoT downlink subframe.

DCI Format

DCI Format N0

DCI format N0 is used for the scheduling of NPUSCH in one UL cell. Thefollowing information is transmitted by means of the DCI format N0.

Flag for format N0/format N1 differentiation (1 bit), subcarrierindication (6 bits), resource assignment (3 bits), scheduling delay (2bits), modulation and coding scheme (4 bits), redundancy version (1bit), repetition number (3 bits), new data indicator (1 bit), DCIsubframe repetition number (2 bits)

DCI Format N1

DCI format N1 is used for the scheduling of one NPDSCH codeword in onecell and random access procedure initiated by a NPDCCH order. The DCIcorresponding to a NPDCCH order is carried by NPDCCH. The followinginformation is transmitted by means of the DCI format N1:

-   -   Flag for format N0/format N1 differentiation (1 bit), NPDCCH        order indicator (1 bit)

Format N1 is used for random access procedure initiated by a NPDCCHorder only if NPDCCH order indicator is set to “1”, format N1 CRC isscrambled with C-RNTI, and all the remaining fields are set as follows:

-   -   Starting number of NPRACH repetitions (2 bits), subcarrier        indication of NPRACH (6 bits), all the remaining bits in format        N1 are set to one.

Otherwise,

-   -   Scheduling delay (3 bits), resource assignment (3 bits),        modulation and coding scheme (4 bits), repetition number (4        bits), new data indicator (1 bit), HARQ-ACK resource (4 bits),        DCI subframe repetition number (2 bits)

When the format N1 CRC is scrambled with a RA-RNTI, then the followingfields among the fields above are reserved.

-   -   New data indicator, HARQ-ACK resource

If the number of information bits in format N1 is less than the numberof information bits in format N0, zeros are appended to format N1 untilthe payload size equals that of format N0.

DCI Format N2

DCI format N2 is used for paging and direct indication. The followinginformation is transmitted by means of the DCI format N2.

Flag for paging/direct indication differentiation (1 bit)

If Flag=0:

-   -   Direct indication information (8 bits), reserved information        bits are added until the size is equal to the size of format N2        with Flag=1

If Flag=1:

-   -   Resource assignment (3 bits), modulation and coding scheme (4        bits), repetition number (4 bits), DCI subframe repetition        number (3 bits)

NPDCCH Related Procedure

A UE shall monitor a set of NPDCCH candidates as configured by higherlayer signalling for control information, where monitoring impliesattempting to decode each of the NPDCCHs in the set according to all themonitored DCI formats.

An NPDCCH search space NS_(k) ^((L′,R)) at aggregation level L′∈{1,2}and repetition level R∈{1,2,4,8,16,32,64,128,256,512,1024,2048} isdefined by a set of NPDCCH candidates, where each candidate is repeatedin a set of R consecutive NB-IoT downlink subframes excluding subframesused for transmission of SI messages starting with subframe k.

The locations of starting subframe k are given by k=k_(b) where k_(b) isthe bth consecutive NB-IoT DL subframe from subframe k0, excludingsubframes used for transmission of SI messages, and b=u·R, and u=0, 1, .. . , R_(max)/R−1, and where subframe k0 is a subframe satisfying thecondition (10n_(f)+└n_(s)/2┘ mod T)=└α_(offset)·T┘, where T=R_(max)·G,T≥4. G and α_(offset) are given by the higher layer parameters.

For Type1-NPDCCH common search space, k=k0 and is determined fromlocations of NB-IoT paging opportunity subframes.

If the UE is configured by higher layers with a NB-IoT carrier formonitoring of NPDCCH UE-specific search space,

the UE monitors the NPDCCH UE-specific search space on the higher layerconfigured NB-IoT carrier,

the UE is not expected to receive NPSS, NSSS, NPBCH on the higher layerconfigured NB-IoT carrier.

otherwise,

the UE monitors the NPDCCH UE-specific search space on the same NB-IoTcarrier on which NPSS/NSSS/NPBCH are detected.

The starting OFDM symbol for NPDCCH given by index l_(NPDCCHStart) inthe first slot in a subframe k and is determined as follows.

If higher layer parameter eutraControlRegionSize is present

l_(NPDCCHStart) is given by the higher layer parametereutraControlRegionSize.

otherwise, l_(NPDCCHStart)=0

Narrowband Reference Signal (NRS)

Before a UE obtains operationModeInfo, the UE may assume narrowbandreference signals are transmitted in subframes #0 and #4 and insubframes #9 not containing NSSS.

When the UE receives higher-layer parameter operationModeInfo indicatingguardband or standalone,

Before the UE obtains SystemInformationBlockType1-NB, the UE may assumenarrowband reference signals are transmitted in subframes #0, #1, #3, #4and in subframes #9 not containing NSSS.

After the UE obtains SystemInformationBlockType1-NB, the UE may assumenarrowband reference signals are transmitted in subframes #0, #1, #3,#4, subframes #9 not containing NSSS, and in NB-IoT downlink subframesand does not expect narrowband reference signals in other downlinksubframes.

When the UE receives higher-layer parameter operationModeInfo indicatinginband-SamePCI or inband-DifferentPCI,

Before the UE obtains SystemInformationBlockType1-NB, the UE may assumenarrowband reference signals are transmitted in subframes #0, #4 and insubframes #9 not containing NSSS.

After the UE obtains SystemInformationBlockType1-NB, the UE may assumenarrowband reference signals are transmitted in subframes #0, #4,subframes #9 not containing NSSS, and in NB-IoT downlink subframes anddoes not expect narrowband reference signals in other downlinksubframes.

Narrowband Primary Synchronization Signal (NPSS)

The sequence d_(l)(n) used for the narrowband primary synchronizationsignal is generated from a frequency-domain Zadoff-Chu sequenceaccording to the following Equation 17.

$\begin{matrix}{{{d_{1}(n)} = {{S(I)} \cdot e^{{- j}\frac{{\pi{un}}{({n + 1})}}{11}}}},{n = 0},1,\cdots,10} & \left\lbrack {{Equation}\mspace{14mu} 17} \right\rbrack\end{matrix}$

where the Zadoff-Chu root sequence index u=5 and S(l) for differentsymbol indices l is given by Table 27.

Table 27 represents an example of S(l).

TABLE 27 Cyclic prefix length S(3), . . . , S(13) Normal 1 1 1 1 −1 −1 11 1 −1 1

The same antenna port shall be used for all symbols of the narrowbandprimary synchronization signal within a subframe.

The UE shall not assume that the narrowband primary synchronizationsignal is transmitted on the same antenna port as any of the downlinkreference signals. The UE shall not assume that the transmissions of thenarrowband primary synchronization signal in a given subframe use thesame antenna port, or ports, as the narrowband primary synchronizationsignal in any other subframe.

The sequences d_(l)(n) shall be mapped to resource elements (k, l) inincreasing order of the first index k=0, 1, . . . , N_(sc) ^(RB)−2 andthen the index l=3, 4, . . . , 2N_(symb) ^(DL)−1 in subframe 5 in everyradio frame. For resource elements (k, l) overlapping with resourceelements where cell-specific reference signals are transmitted, thecorresponding sequence element d(n) is not used for the NPSS but countedin the mapping process.

Narrowband Secondary Synchronization Signal (NSSS)

The sequence d(n) used for the narrowband secondary synchronizationsignal is generated from a frequency-domain Zadoff-Chu sequenceaccording to the following Equation 18.

$\begin{matrix}{{{d(n)} = {{b_{q}(n)} \cdot e^{{- {j2\pi\theta}_{f}}n} \cdot e^{{- j}\frac{{\pi{un}}^{\prime}{({n^{\prime} + 1})}}{131}}}}{Where}{{n = 0},1,\cdots,131}{n^{\prime} = {n\mspace{14mu}{mod}\mspace{14mu} 131}}{m = {n\mspace{14mu}{mod}\mspace{14mu} 128}}{u = {{N_{ID}^{Ncell}{mod}\mspace{14mu} 126} + 3}}{q = \left\lfloor \frac{N_{ID}^{Ncell}}{126} \right\rfloor}} & \left\lbrack {{Equation}\mspace{14mu} 18} \right\rbrack\end{matrix}$

The binary sequence b_(q)(n) is given by Table 35. The cyclic shift θfin frame number n_(f) is given by

$\theta_{f} = {\frac{33}{132}\left( {n_{f}/2} \right){mod}\mspace{14mu}{4.}}$

Table 28 represents an example of b_(q)(n).

TABLE 28 q b_(q)(0), . . ., b_(q)(127) 0 [1 1 1 1 1 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 11 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 11 1 1 1 1] 1 [1 −1 −1 1 −1 1 1 −1 −1 1 1 −1 1 −1 −1 1 −1 1 1 −1 1 −1 −11 1 −1 −1 1 −1 1 1 −1 1 −1 −1 1 −1 1 1 −1 −1 1 1 −1 1 −1 −1 1 −1 1 1 −11 −1 −1 1 1 −1 −1 1 −1 1 1 −1 1 −1 −1 1 −1 1 1 −1 −1 11 −1 1 −1 −1 1 −11 1 −1 1 −1 −1 1 1 −1 −1 1 −1 1 1 −1 1 −1 −1 1 −1 1 1 −1 −1 1 1 −1 1 −1−1 1 −1 1 1 −1 1 −1 −1 1 1 −1 −1 1 −1 1 1 −1] 2 [1 −1 −1 1 −1 1 1 −1 −11 1 −1 1 −1 −1 1 −1 1 1 −1 1 −1 −1 1 1 −1 −1 1 −1 1 1 −1 −1 1 1 −1 1 −1−1 1 1 −1 −1 1 −1 1 1 −1 1 −1 −1 1 −1 1 1 −1 −1 1 1 −1 1 −1 −1 1 1 −1 −11 −1 1 1 −1 −1 1 1 −1 1 −1 −1 1 −1 1 1 −1 1 −1 −1 1 1 −1 −1 1 −1 1 1 −1−1 1 1 −1 1 −1 −1 1 1 −1 −1 1 −1 1 1 −1 1 −1 −1 1 −1 1 1 −1 −1 1 1 −1 1−1 −1 1] 3 [1 −1 −1 1 −1 1 1 −1 −1 1 1 −1 1 −1 −1 1 −1 1 1 −1 1 −1 −1 11 −1 −1 1 −1 1 1 −1 −1 1 1 −1 1 −1 −1 1 1 −1 −1 1 −1 1 1 −1 1 −1 −1 1 −11 1 −1 −1 1 1 −1 1 −1 −1 1 −1 1 1 −1 1 −1 −1 1 1 −1 −1 1 −1 1 1 −1 1 −1−1 1 −1 1 1 −1 −1 1 1 −1 1 −1 −1 1 1 −1 −1 1 −1 1 1 −1 −1 1 1 −1 1 −1 −11 −1 1 1 −1 1 −1 −1 1 1 −1 −1 1 −1 1 1 −1]

The same antenna port shall be used for all symbols of the narrowbandsecondary synchronization signal within a subframe.

The UE shall not assume that the narrowband secondary synchronizationsignal is transmitted on the same antenna port as any of the downlinkreference signals. The UE shall not assume that the transmissions of thenarrowband secondary synchronization signal in a given subframe use thesame antenna port, or ports, as the narrowband secondary synchronizationsignal in any other subframe.

The sequence d(n) shall be mapped to resource elements (k, l) insequence starting with d(0) in increasing order of the first index kover the 12 assigned subcarriers and then the index l over the assignedlast N_(symb) ^(NSSS) symbols in radio frames fulfilling n_(f) mod 2=0,where N_(symb) ^(NSSSS) is given by Table 29.

Table 29 represents an example of the number of NSSS symbols.

TABLE 29 Cyclic prefix length N_(symb) ^(NSSS) Normal 11

OFDM Baseband Signal Generation

If higher-layer parameter operationModeInfo does not indicate‘inband-SamePCI’, and samePCI-Indicator does not indicate ‘samePCI’,time-consecutive signal s_(l) ^((p))(t) on antenna port p of OFDM symboll on a downlink slot is defined by the following Equation 19.

$\begin{matrix}{{s_{l}^{(p)}(t)} = {\sum\limits_{k = {- {\lfloor{N_{sc}^{RB}/2}\rfloor}}}^{{\lceil{N_{sc}^{RB}/2}\rceil} - 1}{a_{k^{( - )},l}^{(p)} \cdot e^{{{j2\pi}{({k + \frac{1}{2}})}}{{\Delta f}{({t - {N_{{CP},l}T_{s}}})}}}}}} & \left\lbrack {{Equation}\mspace{14mu} 19} \right\rbrack\end{matrix}$

For 0≤t<(N_(CP,i)+N)×T_(s), where k⁽⁻⁾=k+└N_(sc) ^(RB)/2┘, N=2048, Δf=15kHz, and a_(k,l) ^((p)) is the content of resource element (k, l) on theantenna port.

If higher-layer parameter operationModeInfo indicates ‘inband-SamePCI’or samePCI-Indicator indicates ‘samePCI’, time-consecutive signal s_(l)^((p))(t), where l′=l+(N_(symb) ^(DL)(n_(s) mod 4)∈{0, . . . , 27}, onthe antenna port p of OFDM symbol l′ is an OFDM symbol index at thestart of the last even-numbered subframe and is defined by the followingEquation 20.

$\begin{matrix}{{s_{l}^{(p)}(t)} = {{\sum\limits_{k = {- {\lfloor{N_{RB}^{DL}{N_{sc}^{RB}/2}}\rfloor}}}^{- 1}{e^{\theta_{k^{( - )}}}{a_{k^{( - )},l}^{(p)} \cdot e^{{j{2\pi}{k\Delta f}}{({t - {N_{{CP},{l^{\prime}{mod}\mspace{14mu} N_{symb}^{DL}}}T_{s}}})}}}}} + {\sum\limits_{k = 1}^{{N_{RB}^{DL}{N_{sc}^{RB}/2}}}{e^{\theta_{k^{( + )}}}{a_{k^{( + )},l}^{(p)} \cdot e^{{j{2\pi}{k\Delta f}}{({t - {N_{{CP},{l^{\prime}{mod}\mspace{14mu} N_{symb}^{DL}}}T_{s}}})}}}}}}} & \left\lbrack {{Equation}\mspace{14mu} 20} \right\rbrack\end{matrix}$

For 0≤t<(N_(CP,i)+N)×T_(s), where k⁽⁻⁾=k+└N_(RB) ^(DL)N_(sc) ^(RB)/2┘and k⁽⁺⁾=k+└N_(RB) ^(DL)N_(sc) ^(RB)/2┘−1,θ_(k,l′)=j2πf_(NB-IoT)T_(s)(N+Σ_(i=0) ^(l′)N_(CP,i mod 7)) if resourceelement (k, l′) is used for Narrowband IoT, and 0 otherwise, andf_(NB-IoT) is the frequency location of the carrier of the NarrowbandIoT PRB minus the frequency location of the center of the LTE signal.

Only normal CP is supported for Narrowband IoT downlink in this releaseof the 3GPP specification.

Initial Access Procedure for NB-IoT

The procedure in which the NB-IoT UE initially accesses the base stationis briefly described in the section “General Signal Transmission andReception Procedure in NB-IoT”. Specifically, the procedure in which theNB-IoT UE initially accesses the base station may consist of a procedurein which the NB-IoT UE searches for an initial cell and a procedure inwhich the NB-IoT UE acquires system information.

In this regard, FIG. 12 illustrates a particular procedure for signalingbetween a UE and a base station (e.g., NodeB, eNodeB, eNB, gNB, etc.)for initial access in the NB-IoT. In the following, a normal initialaccess procedure for NB-IoT, an NPSS/NSSS configuration, and acquisitionof system information (e.g., MIB, SIB, etc.) in the NB-IoT will bedescribed with reference to FIG. 12.

FIG. 12 is a flow chart illustrating an initial access procedure inrelation to a radio system supporting a NB-IoT system.

In FIG. 12 is a flow chart illustrating an example of an initial accessprocedure for NB-IoT, the name of each physical channel and/or physicalsignal may be differently configured or designated depending on thewireless communication system to which the NB-IoT is applied. Forexample, although FIG. 12 illustrates the procedure considering theNB-IoT based on the LTE system, this is merely an example forconvenience of explanation. For example, the contents thereof can beextended and applied to the NB-IoT based on the NR system.

As illustrated in FIG. 12, the NB-IoT is based on following signalstransmitted in the downlink: the primary and secondary narrowbandsynchronization signals (NPSS and NSSS). The NPSS is transmitted over 11sub-carriers from the first subcarrier to the eleventh subcarrier in thesixth subframe of each frame (S1210), and the NSSS is transmitted over12 sub-carriers in the NB-IoT carrier in the tenth subframe for FDD andthe first subframe for TDD of every other frame (S1220).

The NB-IoT UE may receive MIB-NB (MasterInformationBlock-NB) on NBphysical broadcast channel (NPBCH) (S1230).

The MIB-NB uses a fixed schedule with a periodicity of 640 ms andrepetitions made within 640 ms. The first transmission of the MIB-NB isscheduled in subframe #0 of radio frames for which the SFN mod 64=0, andrepetitions are scheduled in subframe #0 of all other radio frames. Thetransmissions are arranged in 8 independently decodable blocks of 80 msduration.

Then, the NB-IoT UE may receive SIB1-NB (SystemInformationBlockType1-NB)on PDSCH (S1240).

The SIB1-NB uses a fixed schedule with a periodicity of 2560 ms. SIB1-NBtransmission occurs in subframe #4 of every other frame in 16 continuousframes. The starting frame for the first transmission of the SIB1-NB isderived from the cell PCID and the number of repetitions within the 2560ms period. The repetitions are made, equally spaced, within the 2560 msperiod. TBS for SystemInformationBlockType1-NB and the repetitions madewithin the 2560 ms are indicated by scheduleInfoSIB1 field in theMIB-NB.

The SI messages are transmitted within periodically occurring timedomain windows (referred to as SI-windows) using scheduling informationprovided in SystemInformationBlockType1-NB. Each SI message isassociated with a SI-window, and the SI-windows of different SI messagesdo not overlap. That is, within one SI-window only the corresponding SIis transmitted. The length of the SI-window is common for all SImessages, and is configurable.

Within the SI-window, the corresponding SI message can be transmitted anumber of times over 2 or 8 consecutive NB-IoT downlink subframesdepending on TBS. The UE acquires the detailed time/frequency domainscheduling information and other information. Examples of otherinformation may include a transport format for the SI messages fromschedulingInfoList field in SystemInformationBlockType1-NB. The UE isnot required to accumulate several SI messages in parallel but may needto accumulate a SI message across multiple SI windows, depending oncoverage condition.

SystemInformationBlockType1-NB configures the SI-window length and thetransmission periodicity for all SI messages.

Further, the NB-IoT UE may receive SIB2-NB(SystemInformationBlockType2-NB) on PDSCH for additional information(S1250).

As illustrated in FIG. 12, NRS refers to a narrowband reference signal.

Random Access Procedure for NB-IoT

The procedure in which the NB-IoT UE randomly accesses the base stationis briefly described in the section “General Signal Transmission andReception Procedure in NB-IoT”. Specifically, the procedure in which theNB-IoT UE randomly accesses the base station may be performed through aprocedure in which the NB-IoT UE transmits a preamble and receives aresponse to the preamble, and the like.

In this regard, FIG. 13 illustrates a particular procedure for signalingbetween a UE and a base station (e.g., NodeB, eNodeB, eNB, gNB, etc.)for random access in the NB-IoT. In the following, a random accessprocedure based on messages (e.g., msg1, msg2, msg3, msg4) used in anormal random access procedure for NB-IoT will be described withreference to FIG. 13.

FIG. 13 is a flow chart illustrating a random access procedure inrelation to a radio system supporting a NB-IoT system.

In FIG. 13 is a flow chart illustrating an example of a random accessprocedure for NB-IoT, the name of each physical channel, physical signaland/or message may be differently configured or designated depending onthe wireless communication system to which the NB-IoT is applied. Forexample, although FIG. 13 illustrates the procedure considering theNB-IoT based on the LTE system, this is merely an example forconvenience of explanation. For example, the contents thereof can beextended and applied to the NB-IoT based on the NR system.

As illustrated in FIG. 13, in case of NB-IoT, an RACH procedure has thesame message flow as LTE with different parameters.

Regarding a random access procedure for NB-IoT, NPRACH that the NB-IoTUE transmits to the base station is described in detail below.

FIG. 14 illustrates a narrowband physical random access channel (NPRACH)region in relation to a radio system supporting a NB-IoT system.

As illustrated in FIG. 14, a random access symbol group consists of acyclic prefix of length and a sequence of identical symbols with totallength. The total number of symbol groups in a preamble repetition unitis denoted by P. The number of time-contiguous symbol groups is denotedby G.

Parameter values of frame structures 1 and 2 are shown in Tables 30 and31, respectively.

TABLE 30 Preamble format G P N T_(CP) T_(SEQ) 0 4 4 5 2048T_(s) 5 ·8192T_(s) 1 4 4 5 8192T_(s) 5 · 8192T_(s) 2 6 6 3 24576T_(s) 3 ·24576T_(s)

TABLE 31 Supported uplink- downlink Preamble format configurations G P NT_(CP) T_(SEQ) 0 1, 2, 3, 4, 5 2 4 1 4778T_(s) 1 · 8192T_(s) 1 1, 4 2 42 8192T_(s) 2 · 8192T_(s) 2 3 2 4 4 8192T_(s) 4 · 8192T_(s) 0-a 1, 2, 3,4, 5 3 6 1 1536T_(s) 1 · 8192T_(s) 1-a 1, 4 3 6 2 3072T_(s) 2 ·8192T_(s)

Due to a specific uplink transmission scheme in NB-IoT, tone informationis further included in an RAR message, and the formula for deriving arandom access radio network temporary identifier (RA-RNTI) is newlydefined. To support the transmission repetitions, the correspondingparameters including an RAR window size and a medium access control(MAC) contention resolution timer are extended.

Referring to FIG. 14, a physical layer random access preamble (i.e.,PRACH) is based on single subcarrier/tone transmission with frequencyhopping for a single user. The PRACH uses subcarrier spacing of 3.75 kHz(i.e., symbol length of 266.7 us), and two cyclic prefix lengths areprovided to support different cell sizes. Frequency hopping is performedbetween random access symbol groups, where each symbol group includesfive symbols and the cyclic prefix, with pseudo-random hopping betweenrepetitions of symbol groups.

NPRACH configuration provided by higher layers (e.g., RRC) may includethe following.

-   -   NPRACH resource periodicity N_(period) ^(NPRACH)        (nprach-Periodicity)    -   Frequency location of the first subcarrier allocated to NPRACH        N_(scoffset) ^(NPRACH) (nprach-SubcarrierOffset)    -   The number of subcarriers allocated to NPRACH N_(sc) ^(NPRACH)        (nprach-NumSubcarriers)    -   The number of starting sub-carriers allocated to contention        based NPRACH random access N_(sc_cont) ^(NPRACH)        (nprach-NumCBRA-StartSubcarriers)    -   The number of NPRACH repetitions per attempt N_(rep) ^(NPRACH)        (numRepetitionsPerPreambleAttempt)    -   NPRACH starting time N_(start) ^(NPRACH) (nprach-StartTime),    -   Fraction for calculating starting subcarrier index for the range        of NPRACH subcarriers reserved for indication of UE support for        multi-tone msg3 transmission N_(MSG3) ^(NPRACH)        (nprach-SubcarrierMSG3-Range Start)

NPRACH transmission can start only N_(start) ^(NPRACH)·30720 T_(s) timeunits after the start of a radio frame fulfilling n_(f) mod(N_(period)^(NPRACH)/10)=0. After transmissions of 4·64(T_(CP)+T_(SEQ)) time units,a gap of 40·30720T_(s) time units shall be inserted.

NPRACH configurations where N_(scoffset) ^(NPRACH)+N_(sc)^(NPRACH)>N_(sc) ^(UL) are invalid.

The NPRACH starting subcarriers allocated to contention based randomaccess are split in two sets of subcarriers, {0, 1, . . . , N_(sc)_(cont) ^(NPRACH)N_(MSG3) ^(NPRACH)−1} and {N_(sc_cont)^(NPRACH)N_(MSG3) ^(NPRACH), . . . , N_(sc) _(cont) ^(NPRACH)−1}, wherethe second set, if present, indicates UE support for multi-tone msg3transmission.

The frequency location of the NPRACH transmission is constrained withinN_(sc) ^(RA)=12 subcarriers. Frequency hopping shall be used within the12 subcarriers, where the frequency location of the i^(th) symbol groupis given by n_(sc) ^(RA)(i)=n_(start)+ñ_(sc) ^(RA)(i), wheren_(start)=N_(scoffset) ^(NPRACH)+└n_(init)/N_(sc) ^(RA)┘·N_(sc) ^(RA),and

${{\overset{\sim}{n}}_{sc}^{RA}(i)} = \left\{ {{\begin{matrix}{\left( {{{\overset{\sim}{n}}_{sc}^{RA}(0)} + {f\left( {i/4} \right)}} \right){mod}\mspace{14mu} N_{sc}^{RA}} & {{i\mspace{14mu}{mod4}} = {{0\mspace{14mu}{and}\mspace{14mu} i} > 0}} \\{{{\overset{\sim}{n}}_{sc}^{RA}\left( {i - 1} \right)} + 1} & {{{i\mspace{14mu}{mod4}} = 1},{{3\mspace{14mu}{and}\mspace{14mu}{{\overset{\sim}{n}}_{sc}^{RA}\left( {i - 1} \right)}{mod2}} = 0}} \\{{{\overset{\sim}{n}}_{sc}^{RA}\left( {i - 1} \right)} - 1} & {{{i\mspace{14mu}{mod4}} = 1},{{3\mspace{14mu}{and}\mspace{14mu}{{\overset{\sim}{n}}_{sc}^{RA}\left( {i - 1} \right)}{mod2}} = 1}} \\{{{\overset{\sim}{n}}_{sc}^{RA}\left( {i - 1} \right)} + 6} & {{i\mspace{14mu}{mod4}} = {{2\mspace{14mu}{and}\mspace{14mu}{{\overset{\sim}{n}}_{sc}^{RA}\left( {i - 1} \right)}} < 6}} \\{{{\overset{\sim}{n}}_{sc}^{RA}\left( {i - 1} \right)} - 6} & {{i\mspace{14mu}{mod4}} = {{2\mspace{14mu}{and}\mspace{14mu}{{\overset{\sim}{n}}_{sc}^{RA}\left( {i - 1} \right)}} \geq 6}}\end{matrix}{f(t)}} = {{\left( {{f\left( {t - 1} \right)} + {\left( {\sum\limits_{n = {{10t} + 1}}^{{10t} + 0}{{c(n)}2^{n - {({{10t} + 1})}}}} \right){{mod}\left( {N_{sc}^{RA} - 1} \right)}} + 1} \right){mod}\mspace{14mu} N_{sc}^{RA}\mspace{20mu}{f\left( {- 1} \right)}} = 0.}} \right.$

where ñ_(SC) ^(RA)(0)=n_(init) mod N_(sc) ^(RA) with n_(init) being thesubcarrier selected by the MAC layer from {0, 1, . . . , N_(sc)^(NPRACH)−1}, and the pseudo random sequence c(n) is given by

c(n)=(x ₁(n+N _(C))+x ₂(n+N _(C)))mod 2

x ₃(n+31)=(x ₁(n+3)+x ₁(n))mod 2

x ₂(n+31)=(x ₂+3)+x ₂(n+2)+x ₂(n))mod 2.

Where N_(C)=1600 and the first m-sequence shall be initialized withx₁(0)=1, x₁(n)=0, n=1, 2, . . . , 30. The initialization of the secondm-sequence may be denoted by c_(init)=Σ_(i=0) ³⁰x₂(i)·2^(i). For NPRACH,the pseudo random sequence generator shall be initialized withc_(init)=N_(ID) ^(Ncell).

In each NPRACH occurrence, {12, 24, 36, 48} subcarriers may besupported. Further, the random access preamble transmission (i.e.,PRACH) may be repeated up to {1, 2, 4, 8, 16, 32, 64, 128} times toenhance coverage.

Discontinuous Reception (DRX) Procedure for NB-IoT

During performing the general signal transmission and receptionprocedure for the NB-IoT, the NB-IoT UE may switch to an idle state(e.g., RRC_IDLE state) and/or an inactive state (e.g., RRC INACTIVEstate) to reduce power consumption. In this case, the NB-IoT UE which isswitched to the idle state and/or the inactive state may be configuredto use a DRX scheme. For example, the NB-IoT UE which is switched to theidle state and/or the inactive state may be configured to monitor anNPDCCH related to paging only in a specific subframe (or frame, slot)according to a DRX cycle configured by the base station. Here, theNPDCCH related to paging may refer to an NPDCCH scrambled with a P-RNTI(Paging Access-RNTI).

FIG. 15 illustrates an example of a discontinuous reception (DRX) schemein an idle state and/or an inactive state.

As shown in FIG. 15, the NB-IoT UE in the RRC_IDLE state monitors onlysome subframes (SFs) with respect to paging occasions (POs) within asubset of radio frames (i.e., paging frames (PFs)). Paging is used totrigger an RRC connection and to indicate a change in system informationfor UE in the RRC_IDLE mode.

If the NB-IoT UE detects a NPDCCH using a paging access radio networktemporary identifier (P-RNTI) in the PO, then the NB-IoT UE decodes acorresponding NPDSCH. A paging message is sent on the NPDSCH and maycontain a list of NB-IoT UEs to be paged and information about whetherpaging is for connection setup or whether system information haschanged. Each NB-IoT UE which finds its ID in this list forwards to itsupper layer that it is paged, and may receive in turn a command toinitialize an RRC connection. If system information is changed, theNB-IoT UE may start to read SIB1-NB and may obtain from the SIB1-NB theinformation, which SIBs have to be read again.

If coverage enhancement repetitions are applied, the PO refers to afirst transmission within the repetition. The PFs and POs are determinedfrom the DRX cycle provided in SIB2-NB and IMSI provided by an USIMcard. The DRX is the discontinuous reception of DL control channel usedto save battery lifetime. Cycles of 128, 256, 512 and 1024 radio framesare supported, corresponding to a time interval between 1.28 sec and10.24 sec. Due to the fact that an algorithm to determine the PFs andPOs depends on the IMSI, different UEs have different paging occasions,which are uniformly distributed in time. It is sufficient for the UE tomonitor one paging occasion within a DRX cycle, and the paging isrepeated in every one of them if there are several paging occasionstherein.

The concept of extended DRX (eDRX) may be applied for NB-IoT as well.This is done using hyper frames (HFNs). If eDRX is supported, then atime interval in which the UE does not monitor the paging messages maybe extended, up to 3 hours. Hence, the UE shall know on which HFN and onwhich time interval within this HFN, the paging time window (PTW), ithas to monitor the paging. The PTW is defined by a start and stop SFN.Within the PTW, the determination of the PFs and POs is done in the sameway as for the non-extended DRX.

FIG. 16 illustrates an example of a DRX cycle.

As shown in FIG. 16, the DRX cycle specifies the periodic repetition ofthe On-duration followed by a possible period of inactivity. The MACentity may be configured by RRC with a DRX functionality that controlsthe UE's PDCCH monitoring activity for the MAC entity's RNTIs (e.g.,C-RNTI). Thus, the NB-IoT UE monitors the PDCCH for a short period(e.g., on-duration), and may stop monitoring the PDCCH for a long period(e.g., opportunity for DRX). When in RRC_CONNECTED, if DRX is configured(i.e., connectedd mode DRX (CDRX)), the MAC entity may monitor the PDCCHdiscontinuously using the DRX operation specified below. Otherwise theMAC entity monitors the PDCCH continuously. For NB-IoT, the PDCCH mayrefer to the NPDCCH. For NB-IoT, an extended DRX cycle of 10.24 s issupported in RRC Connected.

RRC controls DRX operation by configuring the timers onDurationTimer,drx-InactivityTimer, drx-RetransmissionTimer (for HARQ processesscheduled using lms TTI, one per DL HARQ process except for thebroadcast process), drx-RetransmissionTimerShortTTI (for HARQ processesscheduled using short TTI, one per DL HARQ process),drx-ULRetransmissionTimer (for HARQ processes scheduled using lms TTI,one per asynchronous UL HARQ process), drx-ULRetransmissionTimerShortTTI(for HARQ processes scheduled using short TTI, one per asynchronous ULHARQ process), the longDRX-Cycle, the value of the drxStartOffset andoptionally the drxShortCycleTimer and shortDRX-Cycle. A HARQ RTT timerper DL HARQ process (except for the broadcast process) and UL HARQ RTTTimer per asynchronous UL HARQ process are also defined.

First, definitions for the terms are provided as follows.

-   -   onDurationTimer: specifies the number of consecutive        PDCCH-subframe(s) at the beginning of a DRX cycle.    -   drx-InactivityTimer: except for NB-IoT, it specifies the number        of consecutive PDCCH-subframe(s) after the subframe in which a        PDCCH indicates an initial UL, DL or SL user data transmission        for this MAC entity. For NB-IoT, it specifies the number of        consecutive PDCCH-subframe(s) after the subframe in which the        HARQ RTT timer or UL HARQ RTT timer expires.    -   drx-RetransmissionTimer: specifies the maximum number of        consecutive PDCCH-subframe(s) until a DL retransmission is        received.    -   drx-ULRetransmissionTimer: specifies the maximum number of        consecutive PDCCH-subframe(s) until a grant for UL        retransmission is received.    -   drxShortCycleTimer: specifies the number of consecutive        subframe(s) the MAC entity shall follow the short DRX cycle.    -   drxStartOffset: specifies the subframe where the DRX cycle        starts.    -   HARQ RTT Timer: this parameter specifies the minimum amount of        subframe(s) before a DL HARQ retransmission is expected by the        MAC entity.    -   PDCCH-subframe: refers to a subframe with PDCCH. For a FDD        serving cell, this may represent any subframe. For a TDD serving        cell, this may represent a downlink subframe or a subframe        including DwPTS of the TDD UL/DL configuration.    -   Active time: time related to DRX operation, during which the MAC        entity monitors the PDCCH.

When a DRX cycle is configured, the active time includes the time while:

-   -   onDurationTimer or drx-InactivityTimer or        drx-RetransmissionTimer or drx-RetransmissionTimerShortTTI or        drx-ULRetransmissionTimer or drx-ULRetransmissionTimerShortTTI        or mac-ContentionResolutionTimer is running; or    -   a Scheduling Request is sent on PUCCH/SPUCCH and is pending; or    -   an uplink grant for a pending HARQ retransmission can occur and        there is data in the corresponding HARQ buffer for synchronous        HARQ process; or    -   a PDCCH indicating a new transmission addressed to the C-RNTI of        the MAC entity has not been received after successful reception        of a Random Access Response for the preamble not selected by the        MAC entity.

When DRX is configured, the MAC entity shall for each subframe:

-   -   if a HARQ RTT Timer expires in this subframe:    -   if the data of the corresponding HARQ process is not        successfully decoded:    -   start the drx-RetransmissionTimer or        drx-RetransmissionTimerShortTTI for the corresponding HARQ        process.    -   if NB-IoT, start or restart the drx-InactivityTimer.    -   if an UL HARQ RTT Timer expires in this subframe:    -   start the drx-ULRetransmissionTimer or        drx-ULRetransmissionTimerShortTTI for the corresponding HARQ        process.    -   if NB-IoT, start or restart the drx-InactivityTimer.    -   if a DRX Command MAC control element or a Long DRX Command MAC        control element is received:    -   stop onDurationTimer;    -   stop drx-InactivityTimer.    -   if drx-InactivityTimer expires or a DRX Command MAC control        element is received in this subframe:    -   if the Short DRX cycle is configured:    -   start or restart drxShortCycleTimer;    -   use the Short DRX Cycle.    -   if the Short DRX cycle is not configured:    -   use the Long DRX cycle.    -   if drxShortCycleTimer expires in this subframe:    -   use the Long DRX cycle.    -   if the Long DRX Command MAC control element is received:    -   stop drxShortCycleTimer;    -   use the Long DRX cycle.    -   if the Short DRX cycle is used and [(SFN*10)+subframe number]        modulo (shortDRX-Cycle)=(drxStartOffset) modulo        (shortDRX-Cycle); or    -   if the Long DRX Cycle is used and [(SFN*10)+subframe number]        modulo (longDRX-Cycle)=drxStartOffset:    -   if NB-IoT:    -   if there is at least one HARQ process for which neither HARQ RTT        Timer nor UL HARQ RTT Timer is running, start onDurationTimer.    -   if not NB-IoT:    -   start onDurationTimer.    -   during the Active Time, for a PDCCH-subframe, if the subframe is        not required for uplink transmission for half-duplex FDD UE        operation, and if the subframe is not a half-duplex guard        subframe and if the subframe is not part of a configured        measurement gap, and for NB-IoT if the subframe is not required        for uplink transmission or downlink reception other than on        PDCCH:    -   monitor PDCCH;    -   if the PDCCH indicates a DL transmission or if a DL assignment        has been configured for this subframe:    -   if the UE is a NB-IoT UE:    -   start the HARQ RTT Timer for the corresponding HARQ process in        the subframe containing the last repetition of the corresponding        PDSCH reception;    -   if the UE is not a NB-IoT UE:    -   start the HARQ RTT Timer for the corresponding HARQ process;    -   stop the drx-RetransmissionTimer or        drx-RetransmissionTimerShortTTIfor the corresponding HARQ        process.    -   if NB-IoT, stop drx-ULRetransmissionTimer for all UL HARQ        processes.    -   if the PDCCH indicates an UL transmission for an asynchronous        HARQ process or if an UL grant has been configured for an        asynchronous HARQ process for this subframe, or if the PDCCH        indicates an UL transmission for an autonomous HARQ process; or    -   if the uplink grant is a configured grant for the MAC entity's        AUL C-RNTI and if the corresponding PUSCH transmission has been        performed in this subframe:    -   stop the drx-ULRetransmissionTimer or        drx-ULRetransmissionTimerShortTTI for the corresponding HARQ        process;    -   if NB-IoT, stop drx-RetransmissionTimer for all DL HARQ        processes.    -   if the PDCCH indicates a transmission (DL, UL) for a NB-IoT UE:    -   if the NB-IoT UE is configured with a single DL and UL HARQ        process:    -   stop drx-InactivityTimer.    -   stop onDurationTimer.    -   if the PUSCH transmission is completed:    -   stop drx-ULRetransmissionTimer for all UL HARQ processes.    -   if the PDCCH indicates HARQ feedback for one or more HARQ        processes for which UL HARQ operation is autonomous:    -   stop drx-ULRetransmissionTimer for the corresponding HARQ        process(es).

When the NB-IoT UE receives PDCCH, the UE executes the correspondingaction specified in the above in the subframe following the subframecontaining the last repetition of the PDCCH reception where suchsubframe is determined by the starting subframe and the DCI subframerepetition number field in the PDCCH, unless explicitly statedotherwise.

The same Active Time applies to all activated serving cells. For NB-IoT,except for operation in TDD mode, DL and UL transmissions will not bescheduled in parallel. That is, if a DL transmission has been scheduled,an UL transmission will not be scheduled until HARQ RTT Timer of the DLHARQ process has expired (and vice versa).

MTC (Machine Type Communication)

MTC has been mainly designed to use LTE for machine-to-machine (M2M) orInternet of things (IoT). In general, such an application requires notthat much throughput (in most case it needs very low throughput). Thekey requirements of M2M communications include cost reduction, reducedpower consumption, enhanced coverage, etc.

To facilitate MTC, long-term evolution (LTE) Release 12 has introducedsome initial features, such as new low-cost user equipment (UE)category, power saving mode (PSM), and UE assistance information forevolved NodeB (eNB) parameter tuning. The new low-cost UE categoryintroduced in LTE Release 12 is called as Category 0. In order to reducethe baseband and RF complexity of the UE, the Category 0 defines reducedpeak data rate (e.g. 1 Mbps), half duplex operation with relaxed radiofrequency (RF) requirements, and a single receive antenna. The PSMallows the UE to greatly reduce power consumption for applications withdelay-tolerant mobile-originated (MO) traffic in order to achieve yearsof battery lifetime.

Enhanced MTC (eMTC)

In LTE Release 13, additional improvements have been introduced tofurther drive down the cost and power consumption, i.e., eMTC. The eMTCintroduces a set of physical layer features aiming to reduce the costand power consumption of UEs and extending coverage, while at the sametime reusing most of the LTE physical layer procedures. An eMTC UE canbe deployed in any eNB configured to support eMTC and can be servedtogether with other LTE UEs by the same eNB. The main featuresintroduced by eMTC are as follows.

-   -   Narrowband operation: An eMTC UE follows narrowband operation        for the transmission and reception of physical channels and        signals. The eMTC supporting narrowband operation is called a        bandwidth reduced low complexity (BL) UE.

A BL UE can operate in any LTE system bandwidth but with a limitedchannel bandwidth of 6 PRBs (physical resource blocks), whichcorresponds to the maximum channel bandwidth available in a 1.4 MHz LTEsystem, in downlink and uplink.

6 PRBs is selected to allow the eMTC UE to follow the same cell searchand random access procedures as legacy UEs, which use the channels andsignals that occupy 6 RBs: primary synchronization signal (PSS),secondary synchronization signal (SSS), physical broadcast channel(PBCH), and physical random access channel (PRACH).

The eMTC UE can be served by a cell with much larger bandwidth (e.g. 10MHz), but the physical channels and signals transmitted or received bythe eMTC UE are always contained in 6 PRBs.

-   -   Low cost and simplified operation: Many features introduced for        Category 0 UEs are maintained for eMTC UEs, such as a single        receive antenna, reduced soft buffer size, reduced peak data        rate (1 Mbps), and half duplex operation with relaxed switching        time. The following new features are introduced to further        reduce the cost of eMTC UEs. Specifically, reduced transmission        mode support, reduced number of blind decodings for control        channel, no simultaneous reception (a UE is not required to        decode unicast and broadcast data simultaneously), and the        aforementioned narrowband operation have been introduced.    -   Transmission of downlink control information (DCI): Instead of        the legacy control channel (i.e., physical downlink control        channel (PDCCH)), a new control channel called MTC PDCCH        (MPDCCH) is introduced. This new control channel spans up to 6        PRBs in the frequency domain and one subframe in the time        domain. The MPDCCH is similar to enhanced PDCCH (EPDCCH), with        the additional support of common search space for paging and        random access. Furthermore, instead of physical control format        indicator channel (PCFICH) to indicate the size of the control        region, the size of the control region is semi-statically        signalled in the system information block (SIB), so eMTC devices        do not need to decode PCFICH. Further, instead of physical        hybrid automatic repeat request (HARQ) indicator channel (PHICH)        to transmit HARQ feedback for uplink transmissions, there is no        support of the PHICH, and retransmissions are adaptive,        asynchronous, and based on new scheduling assignment received in        an MPDCCH.    -   Extended coverage: The presence of devices in extreme coverage        conditions (e.g. a meter in a basement) requires the UEs to        operate with much lower signal-to-noise ratio (SNR). The        enhanced coverage is obtained by repeating in time almost every        channel beyond one subframe (1 ms) to accumulate enough energy        to decode. Repetition is extended up to 2048 subframes for the        data channels in Release 13 eMTC. The following channels support        repetition in eMTC: physical downlink shared channel (PDSCH),        physical uplink shared channel (PUSCH), MPDCCH, PRACH, physical        uplink control channel (PUCCH), and PBCH. Two modes of operation        are introduced to support coverage enhancement (CE). CE mode A        is defined for small coverage enhancements, for which full        mobility and channel state information (CSI) feedback are        supported. CE mode B is defined for UE in extremely poor        coverage conditions, for which no CSI feedback and limited        mobility are supported.    -   Frequency diversity by RF retuning: In order to reduce the        effect of fading and outages, frequency hopping is introduced        among different narrowbands by RF retuning. This hopping is        applied to the different uplink and downlink physical channels        when repetition is enabled. For example, if 32 subframes are        used for transmission of PDSCH, the 16 first subframes may be        transmitted over the first narrowband; then the RF front-end is        retuned to a different narrowband, and the remaining 16        subframes are transmitted over the second narrowband.

Cell Search for MTC

Cell search is the procedure by which a UE acquires time and frequencysynchronization with a cell and detects the cell ID of that cell. E-UTRAcell search supports a scalable overall transmission bandwidthcorresponding to 6 RBs and upwards. PSS and SSS are transmitted in thedownlink to facilitate cell search. If a resynchronization signal istransmitted in the downlink, it can be used to re-acquire time andfrequency synchronization with the cell. Physical layer provides 504unique cell identities using synchronization signals.

The UE searches for the PSS/SSS in the center 6 PRBs to obtain the cellID, subframe timing information, duplexing mode (time division duplex(TDD), or frequency division duplex (FDD)), and cyclic prefix (CP)length. The PSS uses Zadoff-Chu (ZC) sequence. For frame structure type1 (i.e., FDD), the PSS shall be mapped to the last orthogonal frequencydivision multiplexing (OFDM) symbol in slots 0 and 10. For framestructure type 2 (i.e., TDD), the PSS shall be mapped to the third OFDMsymbol in subframes 1 and 6. The SSS uses an interleaved concatenationof two length-31 binary sequences. The concatenated sequence isscrambled with a scrambling sequence given by the PSS. For FDD, the SSSshall be mapped to OFDM symbol number N_(symb) ^(DL)−2 in slots 0 and10, where N_(symb) ^(DL) is the number of OFDM symbols in a downlinkslot. For TDD, the SSS shall be mapped to OFDM symbol number N_(symb)^(DL)−1 in slots 1 and 11, where N_(symb) ^(DL) is the number of OFDMsymbols in a downlink slot.

System Information Acquisition for MTC

Upon searching the cell by using the PSS/SSS, the UE acquires systeminformation (SI). This is described below with reference to FIG. 17.

FIG. 17 illustrates a general system regarding a system informationacquisition procedure.

The UE applies the system information acquisition procedure to acquirethe access stratum (AS) and non-access stratum (NAS) system informationthat is broadcasted by the E-UTRAN. The procedure applies to UEs inRRC_IDLE and UEs in RRC_CONNECTED.

System information is divided into a master information block (MIB;MasterInformationBlock) and a number of system information blocks(SIBs). The MIB defines the most essential physical layer information ofthe cell required to receive further system information. The MIB istransmitted on PBCH. SIBs other than system information block type-1(SIB1; SystemInformationBlockType1) are carried in SI messages andmapping of SIBs to SI messages is flexibly configurable bySchedulingInfoList included in SystemInformationBlockType1, withrestrictions that: each SIB is contained only in a single SI message,and at most once in that message; only SIBs having the same schedulingrequirement (periodicity) can be mapped to the same SI message; systeminformation block type-1 (SIB2; SystemInformationBlockType2) is alwaysmapped to the SI message that corresponds to the first entry in the listof SI messages in schedulingInfoList. There may be multiple SI messagestransmitted with the same periodicity. SystemInformationBlockType1 andall SI messages are transmitted on DL-SCH. The BL UEs and UEs in CEapply BR version of the SIB or SI messages, for example.

The MIB uses a fixed schedule with a periodicity of 40 ms andrepetitions made within 40 ms. The first transmission of the MIB isscheduled in subframe #0 of radio frames for which the SFN mod 4=0, andrepetitions are scheduled in subframe #0 of all other radio frames. ForTDD/FDD system with a bandwidth larger than 1.4 MHz that supports BL UEsor UEs in CE, it is scheduled in subframe #0 of the same radio frame,and in subframe #5 of the same radio frame for FDD and TDD.

The SystemInformationBlockType1 contain information relevant whenevaluating if a UE is allowed to access a cell and defines thescheduling of other system information blocks. TheSystemInformationBlockType1 uses a fixed schedule with a periodicity of80 ms and repetitions made within 80 ms. The first transmission ofSystemInformationBlockType1 is scheduled in subframe #5 of radio framesfor which the SFN mod 8=0, and repetitions are scheduled in subframe #5of all other radio frames for which SFN mod 2=0.

For BL UEs or UEs in CE, MIB is applied which may be provided withadditional repetitions, while for SIB1 and further SI messages, separatemessages are used which are scheduled independently and with contentthat may differ. The separate instance of SIB1 is named asSystemInformationBlockType1-BR. The SystemInformationBlockType1-BRincludes information such as valid downlink and uplink subframes,maximum support of coverage enhancement, and scheduling information forother SIBs. The SystemInformationBlockType1-BR is transmitted over PDSCHdirectly, without any control channel associated with it. TheSystemInformationBlockType1-BR uses a schedule with a periodicity of 80ms. Transport block size (TBS) for SystemInformationBlockType1-BR andthe repetitions made within 80 ms are indicated via schedulinginformation SIB1-BR in MIB or optionally in theRRCConnectionReconfiguration message including the MobilityControlInfo.Specifically, five reserved bits in the MIB are used in eMTC to conveyscheduling information about SystemInformationBlockType1-BR, includingtime and frequency location, and transport block size. SIB-BR remainsunchanged for 512 radio frames (5120 ms) to allow a large number ofsubframes to be combined.

The SI messages are transmitted within periodically occurring timedomain windows (referred to as SI-windows) using dynamic scheduling.Each SI message is associated with a SI-window, and the SI-windows ofdifferent SI messages do not overlap. That is, within one SI-window onlythe corresponding SI is transmitted. The length of the SI-window iscommon for all SI messages and is configurable. Within the SI-window,the corresponding SI message can be transmitted a number of times in anysubframe other than multimedia broadcast multicast service singlefrequency network (MBSFN) subframes, uplink subframes in TDD, andsubframe #5 of radio frames for which SFN mod 2=0. The UE acquires thedetailed time-domain scheduling (and other information, e.g.,frequency-domain scheduling, used transport format) from decoding systeminformation radio network temporary identity (SI-RNTI) on PDCCH. For aBL UE or a UE in CE, the detailed time/frequency domain schedulinginformation for the SI messages is provided inSystemInformationBlockType1-BR.

The SystemInformationBlockType2 contains common and shared channelinformation. After decoding all the necessary SIBs, the UE is able toaccess the cell by starting a random access procedure.

Random Access Procedure for MTC

The random access procedure is performed for the following events.

-   -   initial access from RRC_IDLE;    -   RRC connection re-establishment procedure;    -   Handover;    -   DL data arrival during RRC_CONNECTED requiring random access        procedure;    -   UL data arrival during RRC_CONNECTED requiring random access        procedure;    -   For positioning purpose during RRC_CONNECTED requiring random        access procedure.

The legacy random access procedure and the random access procedure foreMTC are same in terms of general big picture and overall protocolsequence. That is, the main purpose of the random access procedure is toachieve uplink synchronization and obtain the grant for initial attach.Overall protocol sequence of the random access procedure is made up offour messages, i.e., Msg1, Msg2, Msg3 and Msg4. Basic information aboutthe random access procedure is informed to the UE via SIB2.

On the other hand, the random access procedure for eMTC supports thesignalling of different PRACH resources and different CE levels. Thisprovides some control of the near-far effect for a PRACH by groupingtogether UEs that experience similar path loss. Up to four differentPRACH resources can be signalled, each one with a reference signalreceived power (RSRP) threshold. The UE estimates the RSRP using thedownlink cell-specific reference signal (CRS), and based on themeasurement result selects one of the resources for random access. Eachof these four resources has an associated number of repetitions for aPRACH and number of repetitions for the random access response (RAR).Thus, a UE in bad coverage would need a larger number of repetitions tobe successfully detected by the eNB and need to receive the RAR with thecorresponding number of repetitions to meet their CE level. The searchspaces for RAR and contention resolution messages are also defined inthe system information, separately for each CE level. The UE can beconfigured to be in either CE mode A or CE mode B with a UE-specificsearch space to receive uplink grants and downlink assignments.

A random access procedure for eMTC is described in more detail.

The random access procedure is initiated by a PDCCH order, by the mediaaccess control (MAC) sub-layer itself or by the radio resource control(RRC) sub-layer. The random access procedure on a secondary cell (SCell)shall only be initiated by a PDCCH order. If a MAC entity receives aPDCCH transmission consistent with a PDCCH order masked with its cellRNTI (C-RNTI), and for a specific serving cell, the MAC entity shallinitiate a random access procedure on this serving cell. For randomaccess on the speciall cell (SpCell), a PDCCH order or RRC optionallyindicate the ra-PreambleIndex and the ra-PRACH-MaskIndex; and for randomaccess on an SCell, the PDCCH order indicates the ra-PreambleIndex witha value different from 000000 and the ra-PRACH-MaskIndex. For theprimary timing advance group (pTAG), preamble transmission on PRACH andreception of a PDCCH order are only supported for SpCell.

The following information for a related serving cell is assumed to beavailable before the procedure can be initiated for BL UEs or UEs in CE.

-   -   the available set of PRACH resources associated with each        enhanced coverage level supported in the serving cell for the        transmission of the random access preamble, prach-ConfigIndex.    -   the groups of random access preambles and the set of available        random access preambles in each group (SpCell only):    -   if sizeOfRA-PreamblesGroupA is not equal to        numberOfRA-Preambles:        -   random access preamble groups A and B exist and are            calculated as above;    -   if sizeOfRA-PreamblesGroupA is equal to numberOfRA-Preambles:        -   the preambles that are contained in rndom acess peamble            groups for each enhanced coverage level, if it exists, are            the preambles firstPreamble to lastPreamble.    -   the criteria to select PRACH resources based on RSRP measurement        per CE level supported in the serving cell        rsrp-ThresholdsPrachInfoList.    -   the maximum number of preamble transmission attempts per CE        level supported in the serving cell maxNumPreambleAttemptCE.    -   the number of repetitions required for preamble transmission per        attempt for each CE level supported in the serving cell        numRepetitionPerPreambleAttempt.    -   the configured UE transmitted power of the serving cell        performing the random access procedure, P_(CMAX,c).    -   the RA response window size ra-ResponseWindowSize and the        contention resolution timer mac-ContentionResolutionTimer        (SpCell only) per CE level supported in the serving cell.    -   the power-ramping factor powerRampingStep and optionally        powerRampingStepCE1.    -   the maximum number of preamble transmission TransMax-CE.    -   the initial preamble power preambleInitialReceivedTargetPower        and optionally preambleInitialReceivedTargetPowerCE1.    -   the preamble format based offset DELTA_PREAMBLE.

The random access procedure shall be performed as follows.

1> flush the Msg3 buffer;

1> set the PREAMBLE TRANSMISSION COUNTER to 1;

1> if the UE is a BL UE or a UE in CE:

2> set the PREAMBLE TRANSMISSION COUNTER CE to 1;

2> if the starting CE level has been indicated in the PDCCH order whichinitiated the random access procedure, or if the starting CE level hasbeen provided by upper layers:

3> the MAC entity considers itself to be in that CE level regardless ofthe measured RSRP;

2> else:

3> if the RSRP threshold of CE level 3 is configured by upper layers inrsrp-ThresholdsPrachInfoList and the measured RSRP is less than the RSRPthreshold of CE level 3 and the UE is capable of CE level 3 then:

4> the MAC entity considers to be in CE level 3;

3> else if the RSRP threshold of CE level 2 is configured by upperlayers in rsrp-ThresholdsPrachInfoList and the measured RSRP is lessthan the RSRP threshold of CE level 2 and the UE is capable of CE level2 then:

4> the MAC entity considers to be in CE level 2;

3> else if the measured RSRP is less than the RSRP threshold of CE level1 as configured by upper layers in rsrp-ThresholdsPrachInfoList then:

4> the MAC entity considers to be in CE level 1;

3> else:

4> the MAC entity considers to be in CE level 0;

1> set the backoff parameter value to 0 ms;

1> proceed to the selection of the random access resource.

A random access preamble (referred to as “Msg1”) is transmitted overPRACH. A UE randomly selects one random access preamble from a set ofrandom access preambles indicated by system information or a handovercommand, selects a PRACH resource able to transmit the random accesspreamble, and transmits the same.

The physical layer random access preamble consists of a cyclic prefix oflength T_(CP) and a sequence part of length T_(SEQ). The parametervalues are listed in Table 32 below and may depend on the framestructure and the random access configuration. Higher layers control thepreamble format.

TABLE 32 Preamble format T_(CP) T_(SEQ) 0  3168 · T_(s) 24576 · T_(s) 121024 · T_(s) 24576 · T_(s) 2  6240 · T_(s) 2 · 24576 · T_(s) 3 21024 ·T_(s) 2 · 24576 · T_(s) 4   448· T_(s)  4096 · T_(s)

The transmission of a random access preamble, if triggered by the MAClayer, is restricted to certain time and frequency resources. Theseresources are enumerated in increasing order of the subframe numberwithin the radio frame and the PRBs in the frequency domain such thatindex 0 corresponds to the lowest numbered PRB and subframe within theradio frame. PRACH resources within the radio frame are indicated by aPRACH configuration index.

For BL/CE UEs, for each PRACH CE level, there is a PRACH configurationconfigured by higher layers with a PRACH configuration index(prach-ConfigurationIndex), a PRACH frequency offset n _(PRBoffset)^(RA) (prach-FrequencyOffset), a number of PRACH repetitions per attemptN_(rep) ^(PRACH) (numRepetitionPerPreambleAttempt) and optionally aPRACH starting subframe periodicity N_(start) ^(PRACH)(prach-StartingSubframe). PRACH of preamble format 0-3 is transmittedN_(rep) ^(PRACH)≥1 times, whereas PRACH of preamble format 4 istransmitted one time only.

For BL/CE UEs and for each PRACH CE level, if frequency hopping isenabled for a PRACH configuration by the higher-layer parameterprach-HoppingConfig, the value of the parameter n_(PRB offset) ^(RA)depends on the system frame number (SFN) and the PRACH configurationindex and is given as follows.

-   -   In case the PRACH configuration index is such that a PRACH        resource occurs in every radio frame,

$n_{{PRB}\mspace{14mu}{offset}}^{RA} = \left\{ {\begin{matrix}{\overset{\_}{n}\;}_{{PRB}\mspace{14mu}{offset}}^{RA} & {{{if}\mspace{14mu} n_{f}\mspace{14mu}{mod}\mspace{14mu} 2} = 0} \\{\left( {{\overset{\_}{n}}_{{PRB}\mspace{14mu}{offset}}^{RA} + f_{{PRB},{hop}}^{PRACH}} \right){mod}\mspace{14mu} N_{RB}^{UL}} & {{{if}\mspace{14mu} n_{f}\mspace{14mu}{mod}\mspace{14mu} 2} = 1}\end{matrix},} \right.$

$n_{{PRB}\mspace{14mu}{offset}}^{RA} = \left\{ \begin{matrix}{\overset{\_}{n}\;}_{{PRB}\mspace{14mu}{offset}}^{RA} & {{{if}\mspace{14mu}\left\lfloor \frac{n_{f}\mspace{14mu}{mod}\mspace{14mu} 4}{2} \right\rfloor} = 0} \\{\left( {{\overset{\_}{n}}_{{PRB}\mspace{14mu}{offset}}^{RA} + f_{{PRB},{hop}}^{PRACH}} \right){mod}\mspace{14mu} N_{RB}^{UL}} & {{{if}\mspace{14mu}\left\lfloor \frac{n_{f}\mspace{14mu}{mod}\mspace{14mu} 4}{2} \right\rfloor} = 1}\end{matrix} \right.$

-   -   otherwise,

where n_(f) is the system frame number corresponding to the firstsubframe for each PRACH repetition, f_(PRB,hop) ^(PRACH) corresponds toa cell-specific higher-layer parameter prach-HoppingOffset. If frequencyhopping is not enabled for the PRACH configuration, then n_(PRB offset)^(RA)=n _(PRB offset) ^(RA).

For BL/CE UEs, only a subset of the subframes allowed for preambletransmission are allowed as starting subframes for the N_(rep) ^(PRACH)repetitions. The allowed starting subframes for a PRACH configurationare determined as follows:

-   -   Enumerate the subframes that are allowed for preamble        transmission for the PRACH configuration as n_(sf) ^(RA)=0, . .        . N_(sf) ^(RA)−1, where n_(sf) ^(RA)=0 and n_(sf) ^(RA)=N_(sf)        ^(RA)−1 correspond to the two subframes allowed for preamble        transmission with the smallest and the largest absolute subframe        number n_(sf) ^(abs), respectively.    -   If a PRACH starting subframe periodicity N_(start) ^(PRACH) is        not provided by higher layers, the periodicity of the allowed        starting subframes in terms of subframes allowed for preamble        transmission is N_(rep) ^(PRACH). The allowed starting subframes        defined over n_(sf) ^(RA)=0, . . . N_(sf) ^(RA)−1 are given by        jN_(rep) ^(PRACH), where j=0, 1, 2 . . .    -   If a PRACH starting subframe periodicity N_(start) ^(PRACH) is        provided by higher layers, it indicates the periodicity of the        allowed starting subframes in terms of subframes allowed for        preamble transmission. The allowed starting subframes defined        over n_(sf) ^(RA)=0, . . . N_(sf) ^(RA)−1 are given by        jN_(start) ^(PRACH)+N_(rep) ^(PRACH), j where=0, 1, 2 . . .    -   No starting subframe defined over n_(sf) ^(RA)=0, . . . N_(sf)        ^(RA)−1 such that n_(sf) ^(RA)>N_(sf) ^(RA)−N_(rep) ^(PRACH) is        allowed.

The random access preambles are generated from Zadoff-Chu (ZC) sequenceswith zero correlation zone, generated from one or several rootZadoff-Chu sequences. The network configures the set of preamblesequences the UE is allowed to use.

There are up to two sets of 64 preambles available in a cell, where Set1 corresponds to higher layer PRACH configuration usingprach-ConfigurationIndex and prach-FrequencyOffset, and Set 2, ifconfigured, corresponds to higher layer PRACH configuration usingprach-ConfigurationIndexHighSpeed and prach-FrequencyOffsetHighSpeed.

The set of 64 preamble sequences in a cell may be found by includingfirst, in the order of increasing cyclic shift, all the available cyclicshifts of a root Zadoff-Chu sequence with the logical indexrootSequenceIndexHighSpeed (for Set 2, if configured) or with thelogical index RACH_ROOT_SEQUENCE (for Set 1), where bothrootSequenceIndexHighSpeed and RACH_ROOT_SEQUENCE are broadcasted aspart of the system information. Additional preamble sequences, in case64 preambles cannot be generated from a single root Zadoff-Chu sequence,are obtained from the root sequences with the consecutive logicalindexes until all the 64 sequences are found.

2. After the random access preamble is transmitted, the UE attempts toreceive a random access response (may be referred to as “Msg2”) hereofgenerated by MAC on DL-SCH within a random access response receptionwindow indicated by the system information or the handover command. Indetail, the random access response information is transmitted in theform of a MAC PDU, and the MAC PDU is transferred on a physical downlinkshared channel (PDSCH).

In order to allow the UE to properly receive the information transmittedon the PDSCH, a PDCCH is also transferred together. For eMTC, the MPDCCHis newly introduced. MPDCCH carries downlink control information and istransmitted across N_(rep) ^(MPDCCH)≥1 consecutive BL/CE DL subframes.Within each of the N_(rep) ^(MPDCCH), BL/CE DL subframes, an MPDCCH istransmitted using an aggregation of one or several consecutive enhancedcontrol channel elements (ECCEs), where each ECCE consists of multipleenhanced resource element groups (EREGs). Furthermore, the narrowbandfor MPDCCH is determined by SIB2 parameter mpdcch-NarrowbandsToMonitor.

The MPDCCH includes information regarding a UE which is to receive thePDSCH, frequency and time information of radio resource of the PDSCH, atransmission format of the PDSCH, and the like. When the UE successfullyreceives the MPDCCH destined therefor, the UE appropriately receives therandom access response transmitted on the PDSCH according to theinformation items of the MPDCCH. The random access response includes arandom access preamble identifier (ID), a UL grant (uplink radioresource), C-RNTI, and a time alignment command (TAC). In the above, thereason why the random access preamble identifier is required is that,since a single random access response may include random access responseinformation for one or more UEs, so the random access preambleidentifier informs for which UE the UL grant, temporary C-RNTI, and TACare valid. The random access preamble identifier is identical to arandom access preamble selected by the UE in step 1. UL grant includedin the random access response depends on CE mode.

3. When the UE receives the random access response valid therefor, theUE processes the information items included in the random accessresponse. That is, the UE applies the TAC and stores the temporaryC-RNTI. Also, the UE transmits scheduled data (may be referred to as“Msg3”) stored in a buffer thereof or newly generated data to the basestation by using the UL grant on UL-SCH. In this case, an identifier ofthe UE should be included in the data included in the UL grant. Thereason is because, in the contention based random access procedure, thebase station cannot determine which UEs perform the random accessprocedure, so in order to resolve collision later, the base stationshould identify UEs. Also, there are two types of methods for includingan identifier of the UE. A first method is that when the UE has a validcell identifier already allocated in the corresponding cell before therandom access procedure, the UE transmits its cell identifier throughthe UL grant. When the UE has not been allocated a valid cell identifierbefore the random access procedure, the UE includes its uniqueidentifier (e.g., S-TMSI) or a random ID in data and transmits the same.In general, the unique identifier is longer than a cell identifier. Whenthe UE transmits the data through the UL grant, the UE starts acontention resolution timer.

4. After the UE transmits the data including its identifier through theUL grant included in the random access response, the UE waits for aninstruction from the base station for a contention resolution (may bereferred to as “Msg4”). That is, in order to receive a particularmessage, the UE attempts to receive the MPDCCH. There are two methodsfor receiving the MPDCCH. As described above, if the identifier of theUE transmitted via the UL grant is a cell identifier, the UE attempts toreceive the MPDCCH by using its cell identifier, and if the identifieris a unique identifier, the UE attempts to receive the MPDCCH by usingthe temporary C-RNTI included in the random access response. Hereafter,in the former case, when the MPDCCH is received through its cellidentifier before the contention resolution timer expires, the UEdetermines that the random access procedure has been normally performed,and terminates the random access procedure. In the latter case, when theUE receives the MPDCCH through the temporary cell identifier before thecontention resolution time expires, the UE checks data transferred bythe PDSCH indicated by the MPDCCH. If the data content includes itsunique identifier, the UE determines that the random access procedurehas been normally performed, and terminates the random access procedure.

At completion of the random access procedure, the MAC entity shall:

-   -   discard explicitly signalled ra-PreambleIndex and        ra-PRACH-MaskIndex;    -   flush the HARQ buffer used for transmission of the MAC PDU in        the Msg3 buffer.

Extended Discontinuous Reception (DRX)

Extended DRX cycles are introduced in LTE Release 13 for both idle andconnected modes, thus enabling further UE power savings when the UE isnot required to be reachable as frequently. For the idle mode, themaximum possible DRX cycle length is extended to 43.69 min, while forconnected mode the maximum DRX cycle is extended up to 10.24 sec. Sincethe SFN wraps around every 1024 radio frames (i.e., 10.24 sec), eDRXintroduces hyper-SFN (H-SFN) cycles to enable an extended common timereference to be used for paging coordination between the UE and thenetwork. The H-SFN is broadcast by the cell and increments by one whenthe SFN wraps around (i.e., every 10.24 sec). The maximum eDRX cyclecorresponds to 256 hyper-frames.

A UE configured with an eDRX cycle in the idle mode monitors the controlchannel for paging during a paging transmission window (PTW). The PTW isperiodic with starting time defined by a paging hyper-frame (PH), whichis based on a formula that is known by the mobility managing entity(MME), UE, and eNB as a function of the eDRX cycle and UE identity.During the PTW, the UE monitors paging according to the legacy DRX cycle(TDRX) for the duration of the PTW or until a paging message is receivedfor the UE, whichever is earlier. During the idle time outside of thePTW, the UE power (Pdeep_sleep) will generally be much lower than thesleep power within the PTW (Psleep). The transition to the deep-sleepstate is not instantaneous and requires some preparation time for the UEto load or save the context into non-volatile memory. Hence, in order totake full advantage of power savings in deep-sleep state, the eDRX cycle(TeDRX) should be sufficiently long and the PTW as small as possible.

The NR supports multiple numerologies (or subcarrier spacing (SCS)) forsupporting various 5G services. For example, the NR supports a wide areain traditional cellular bands when the SCS is 15 kHz, supportsdense-urban, lower latency, and wider carrier bandwidth when the SCS is30 kHz/60 kHz, and supports a bandwidth larger than 24.25 GHz toovercome a phase noise when the SCS is 60 kHz or higher.

An NR frequency band is defined as frequency ranges of two types (FR1and FR2). The FR1 and FR2 may be configured as the following Table 33.The FR2 may mean millimeter wave (mmW).

TABLE 33 Frequency Corresponding Range designation frequency rangeSubcarrier Spacing FR1   450 MHz-7125 MHz 15, 30, 60 kH z FR2 24250MHz-52600 MHz 60, 120, 240 kHz

Narrowband (NB)-LTE is a system for supporting low complexity and lowpower consumption with a system BW corresponding to 1 physical resourceblock (PRB) of the LTE system. This may be mainly used as acommunication method for implementing internet of things (IoT) bysupporting devices such as machine-type communication (MTC) in acellular system. By using, as OFDM parameters such as subcarrier spacingof the existing LTE, the same parameters as LTE, there is an advantagein that 1 PRB is allocated to the legacy LTE band for NB-LTE withoutadditional band allocation, thereby enabling the frequency to be usedefficiently. In case of downlink, a physical channel of NB-LTE isdefined as narrowband primary synchronization signal (NPSS)/narrowbandsecondary synchronization signal (NSSS), narrowband physical broadcastchannel (NPBCH), NPDCCH/NEPDCCH, NPDSCH, etc., and N is added todistinguish from LTE.

In Legacy LTE and LTE eMTC, semi-persistent scheduling (SPS) has beenintroduced and used. First, the UE receives SPS configuration setupinformation via RRC signaling. Subsequently, if the UE receives SPSactivation DCI (with SPS-C-RNTI) from the base station, the SPS operatesusing SPS configuration information received via RRC signaling, resourcescheduling information included in corresponding DCI, MCS information,etc.

If the UE receives SPS release DCI (with SPS-C-RNTI) from the basestation, the SPS is released. Thereafter, if the UE receives again theSPS activation DCI (with SPS-C-RNTI), the SPS operates as describedabove. If the UE receives the SPS release DCI (with SPS-C-RNTI) and thenreceives SPS configuration release information via RRC signaling, thecorresponding UE cannot detect the SPS activation DCI until receivingthe SPS configuration setup information again (because the UE does notknow the SPS-C-RNTI value).

The phrase ‘monitoring a search space’ used in the present disclosuremeans a process of decoding an NPDCCH for a specific area according to aDCI format to be received through the search space and then scramblingthe corresponding CRC with a preset specific RNTI value to check whethera desired value is correct. In addition, since each UE in the NB-LTEsystem recognizes a single PRB as a respective carrier, it can be saidthat a PRB mentioned in the present disclosure has the same meaning as acarrier. DCI formats N0, N1, and N2 mentioned in the present disclosurerefer to DCI formats N0, N1, and N2 in the 3GPP TS 36.212 standard.

In addition, the above contents (3GPP system, frame structure, NB-IoTsystem, etc.) may be applied in combination with methods according tothe present disclosure described below, or may be supplemented toclarify technical features of methods described in the presentdisclosure.

A resource selecting method described in the present disclosure may berespectively applied or applied in combination with one or more of theinitial access (IA), random access (RA) and discontinuous reception(DRX) procedures described above

1. Initial Access (IA)

A SPS related operation in the NB-IoT system described in the presentdisclosure may be performed after the initial access procedure describedabove.

First, it will be described in relation to the UE operation.

A UE may be configured with parameters (or control information) definedor configured to perform the methods described in the present disclosurefrom the base station (1) via signaling (e.g., DCI, MAC CE, referencesignal, synchronization signal, etc.) received through the initialaccess procedure or (2) via signaling (e.g., DCI, MAC CE, referencesignal, synchronization signal, RRC signaling, etc.) received in the RRCconnected state after the initial access procedure.

And, the UE may perform the methods described in the present disclosureafter the initial access based on the parameters received as above.

Next, it will be described in relation to a base station operation.

The base station (1) may configure parameters (or control information)to perform the methods described in the present disclosure through theinitial access procedure and transmit the configured parameters to theUE via specific signaling (e.g., DCI, MAC CE, reference signal,synchronization signal, etc.) or (2) may configure the parameters (orcontrol information) in an RRC connected state after the initial accessprocedure and transmit the configured parameters to the UE via specificsignaling (e.g., DCI, MAC CE, reference signal, synchronization signal,RRC signaling, etc.)

In addition, the base station may perform the methods described in thepresent disclosure after the initial access based on the correspondingparameters.

2. Random Access (RA)

A SPS related operation in the NB-IoT system described in the presentdisclosure may be performed after the random access procedure describedabove.

First, it will be described in relation to the UE operation.

A UE may be configured with parameters (or control information) definedor configured to perform the methods described in the present disclosurefrom the base station (1) via signaling (e.g., DCI, MAC CE, referencesignal, synchronization signal, etc.) received through the random accessprocedure or (2) via signaling (e.g., DCI, MAC CE, reference signal,synchronization signal, RRC signaling, etc.) received in the RRCconnected state after the random access procedure.

And, the UE may perform the methods described in the present disclosureafter the random access based on the parameters received as above.

Next, it will be described in relation to a base station operation.

The base station (1) may configure parameters (or control information)to perform the methods described in the present disclosure through therandom access procedure and transmit the configured parameters to the UEvia specific signaling (e.g., DCI, MAC CE, reference signal,synchronization signal, etc.) or (2) may configure the parameters (orcontrol information) in an RRC connected state after the random accessprocedure and transmit the configured parameters to the UE via specificsignaling (e.g., DCI, MAC CE, reference signal, synchronization signal,RRC signaling, etc.)

In addition, the base station may perform the methods described in thepresent disclosure after the initial access based on the correspondingparameters.

3. Discontinuous Reception (DRX)

A SPS related operation in the NB-IoT system described in the presentdisclosure may be performed after receiving NPDCCH (or MPDCCH) duringon-duration of DRX cycle described above and transitioning to the RRCconnected state.

First, it will be described in relation to the UE operation.

A UE may be configured with parameters (or control information) definedor configured to perform the methods described in the present disclosurefrom the base station (1) via signaling (e.g., DCI, MAC CE, referencesignal, synchronization signal, etc.) received in relation to the DRXoperation, or (2) via a paging message, or (3) via RRC signaling in theRRC connected state.

And, the UE may receive the paging in DRX and perform the methodsdescribed in the present disclosure in the RRC connected state based onthe parameters received as above.

Next, it will be described in relation to a base station operation.

The base station (1) may configure parameters (or control information)to perform the methods described in the present disclosure through a DRXrelated procedure and transmit the configured parameters to the UE viaspecific signaling (e.g., DCI, MAC CE, reference signal, synchronizationsignal, RRC signaling, etc.), or (2) may transmit the parameters (orcontrol information) to the UE via the paging message, or (3) maytransmit the parameters (or control information) to the UE via RRCsignaling.

In addition, the base station may perform the methods described in thepresent disclosure after transmitting the paging in DRX based on thecorresponding parameters.

However, the above-described contents are merely an example, and theparameter configuration and the UE/base station operation for performingthe methods described in the present disclosure may be performed inrelation to the operations mentioned throughout the present disclosure.

A physical layer process for narrowband physical broadcast channel(NPBCH) (NPBCH) is described in detail below.

Scrambling

Scrambling is done according to clause 6.6.1 of 3GPP TS 36.211 withM_(bit) denoting the number of bits to be transmitted on the NPBCH.M_(bit) equals 1600 for normal cyclic prefix. The scrambling sequence isinitialized with c_(init)=N_(ID) ^(Ncell) in radio frames fulfillingn_(f) mod 64=0.

Modulation

Modulation is done according to clause 6.6.2 of TS 36.211 using themodulation scheme in Table 10.2.4.2-1.

Table 34 represents an example of a modulation scheme for NPBCH.

TABLE 34 Physical channel Modulation scheme NPBCH QPSK

Layer Mapping and Precoding

Layer mapping and precoding are done according to clause 6.6.3 of 3GPPTS 36.211 with P∈{1,2}. The UE assumes antenna ports R₂₀₀₀ and R₂₀₀₁ areused for the transmission of the narrowband physical broadcast channel.

Mapping to Resource Elements

The block of complex-valued symbols y^((p))(0), . . .y^((p))(M_(symb)−1) each antenna port is transmitted in subframe 0during 64 consecutive radio frames starting in each radio framefulfilling n_(f) mod 64=0 and shall be mapped in sequence starting withy(0) to resource elements (k, l). The mapping to resource elements (k,l) not reserved for transmission of reference signals shall be inincreasing order of first the index k, then the index l. After mappingto a subframe, the subframe is repeated in subframe 0 in the 7 followingradio frames, before continuing the mapping of y^((p))(⋅) to subframe 0in the following radio frame. The first three OFDM symbols in a subframeare not be used in the mapping process.

For the purpose of the mapping, the UE assumes cell-specific referencesignals for antenna ports 0-3 and narrowband reference signals forantenna ports 2000 and 2001 being present irrespective of the actualconfiguration. The frequency shift of the cell-specific referencesignals shall be calculated by replacing N_(ID) ^(cell) with N_(ID)^(Ncell) in the calculation of shirt in clause 6.10.1.2 of 3GPP TS36.211.

Next, information related to MIB-NB and SIBN1-NB is described in detail.

MasterinformationBlock-NB

The MasterinformationBlock-NB includes system information transmitted onBCH.

Signalling radio bearer: N/A

RLC-SAP: TM

Logical channel: BCCH

Direction: E-UTRAN to UE

Table 35 below represents an example of MasterinformationBlock-NBformat.

TABLE 35 -- ASN1START MasterInformationBlock-NB ::= SEQUENCE { systemFrameNumber-MSB-r13  BIT STRING (SIZE (4)),  hyper:SBN-LSB-r13 BIT STRING (SIZE (2)),  scheduling:InfoSFBI-r13  INTEGER (0..15), systemInfoValueTNG-r13  INTEGER (0..31),  ab-Enabled-r13  BOOLEAN. operationModeInfo-r13  CHOICE {   inband-SamePCl-r13  Inband-SamePCl-NB-r13   inband-DifferencePCl-r13  Inband-DifferentPCl-NB-r13.   guardband-r13   Guardband-NB-r13.  standalone-r13   Standalone-NB-r13  }  spare   BIT STRING (SIZE (11))}

Guardband-NB-r13 ::= SEQUENCE {  

-r13  

Offset-NB-r13  spare    BIT STRING (SIZE (

)) } Inband-SamePC-NB-r13 ::= SEQUENCE {  extra-CRS-Sequenceinfo-r13 INTEGER {0..31) } Inband-DifferencePCl-NB-r13 SEQUENCE { extra-NumCRS-Ports-r13  ENUMERATED {same, four},  rasterOffset-r13  

Offset-NB-r13.  spare   BIT STRING (SIZE (2)) } Standalone-NB-r13 ::=SEQUENCE {  spare   BIT STRING (SIZE (5)) } --ASN1STOP

indicates data missing or illegible when filed

Table 36 below represents description of MasterinformationBlock-NBfield.

TABLE 36 MasterInformationBlock-NB Field Descriptions ab-Enabled ValueTRUE indicates that access barring is enabled and that the UE shallacquire SystemInformationBlockType14-NB before initiating RRC connectionestablishment or resume. eutra-CRS-SequenceInfo Information of thecarrier containing NPSS/NSSS/NPBCH. Each value is associated with anE-UTRA PRB index as an offset from the middle of the LTE system sortedout by channel raster offset. eutra-NumCRS-Ports Number of E-UTRA CRSantenna ports, either the same number of ports as NRS or 4 antennaports. hyperSFN-LSB Indicates the 2 least significant bits of hyper SFN.The remaining bits are present in SystemInformationBlockType1-NB.operationModeInfo Deployment scenario (in-band/guard-band/standalone)and related information. See TS 36.211 [21] and TS 36.213 [23].Inband-SamePCI indicates an in-band deployment and that the NB-IoT andLTE cell share the same physical cell id and have the same number of NRSand CRS ports. Inband-DifferentPCI indicates an in-band deployment andthat the NB-IoT and LTE cell have different physical cell ID. guardbandindicates a guard-band deployment. standalone indicates a standalonedeployment. rasterOffset NB-IoT offset from LTE channel raster. Unit inkHz in set {−7.5, −2.5, 2.5, 7.5}. schedulingInfoSIB1 This fieldcontains an index to a table specified in TS 36.213 [23, Table16.4.1.3-3] that defines SystemInformationBlockType1-NB schedulinginformation. systemFrameNumber-MSB Defines the 4 most significant bitsof the SFN. As indicated in TS 36.211 [21], the 6 least significant bitsof the SFN are acquired implicitly by decoding the NPBCH.systemInfoValueTag Common for all SIBs other than MIB-NB, SIB14-NB andSIB16-NB.

SystemInformationBlockType1-NB

The SystemInformationBlockType1-NB message contains information relevantwhen evaluating if a UE is allowed to access a cell and defines thescheduling of other system information.

Signalling radio bearer: N/A

RLC-SAP: TM

Logical channel: BCCH

Direction: E-UTRAN to UE

Table 37 represents an example of SystemInformationBlockType1(SIB1)-NBmessage.

TABLE 37 -- ASN1 START SystemInformationBlockType1-NB ::= SEQUENCE { hyperSFN-MSB-r13 1BIT STRING (SIZE (8)),  cellAccessRelatedInfo-r131SEQUENCE {   plmn-IdentityList-r13 2PLMN-IdentityList-NB-r13,  trackingAreaCode-r13 2TrackingAreaCode,   cellIdentity-r131CellIdentity,   cellBarred-r13 2ENUMERATED {barred, notBarred},  intraFreqReselection-r13 2ENUMERATED {allowed, notAllowed}  }, cellSelectionInfo-r13 1SEQUENCE {   q-RxLevMin-r13 3Q-RxLevMin,  q-QualMin-r13 2Q-QualMin-r9  },  p-Max-r13 1P-Max OPTIONAL, -- Need OP freqBandIndicator-r13 1FreqBandIndicator-NB-r13,  freqBandInfo-r131NS-PmaxList-NB-r13 OPTIONAL,  --Need OR  multiBandInfoList-r131MultiBandInfoList-NB-r13 OPTIONAL,  --Need OR  downlinkBitmap-r132DL-Bitmap-NB-r13  OPTIONAL, -- Need OP,  eutraControlRegionSize-r132ENUMERATED {n1, n2, n3}  OPTIONAL, -- Cond inband nrs-CRS-PowerOffset-r13 2ENUMERATED {dB-6, dB-4dot77, dB- 3,4dB-1dot77, dB0, dB 1, 4dB1dot23, dB2, dB3, 4dB4, dB4dot23, dB5, 4dB6,dB7, dB8, 4dB9} OPTIONAL, -- Cond inband-SamePCI  schedulingInfoList-r131SchedulingInfoList-NB-r13,  si-WindowLength-r13 2ENUMERATED {ms160,ms320, ms480,  ms640, 4ms960, ms1280, ms1600, spare1}, si-RadioFrameOffset-r13 2INTEGER (1..15) OPTIONAL, --Need OP systemInfoValueTagList-r13 2SystemInfoValueTagList-NB-r13  OPTIONAL, --Need OR  lateNonCriticalExtension 1OCTET STRING OPTIONAL, nonCriticalExtension 1SEQUENCE { }  OPTIONAL } PLMN-IdentityList-NB-r13::= SEQUENCE (SIZE (1..maxPLMN-r11)) OF PLMN- IdentityInfo-NB-r13PLMN-IdentityInfo-NB-r13 := SEQUENCE {  plmn-Identity-r132PLMN-Identity,  cellReservedForOperatorUse-r13 3ENUMERATED {reserved,notReserved},  attachWithoutPDN-Connectivity-r13 3ENUMERATED{true}OPTIONAL  --Need OP } SchedulingInfoList-NB-r13 ::= SEQUENCE (SIZE(1..maxSI-Message-NB-r13)) OF SchedulingInfo-NB-r13SchedulingInfo-NB-r13::= SEQUENCE {  si-Periodicity-r13 0ENUMERATED{rf64, rf128, rf256, rf512, 3rf1024, rf2048, rf4096, spare}, si-RepetitionPattern-r13 1ENUMERATED {every2ndRF, every4thRF, 4every8thRF, every16thRF},  sib-MappingInfo-r13 1SIB-MappingInfo-NB-r13, si-TB-r13 ENUMERATED {b56, b120, b208, b256, b328, b440, b552, b680} }SystemInfoValueTagList-NB-r13 ::= SEQUENCE (SIZE (1..maxSI-Message-NB-r13)) OF 1SystemInfoValueTagSI-r13SIB-MappingInfo-NB-r13 ::= 1SEQUENCE (SIZE (0..maxSIB-1)) OF SIB-Type-NB-r13 SIB-Type-NB-r13 ::= 1ENUMERATED { 1sibType3-NB-r13,sibType4-NB-r13, sibType5- NB-r13, 1sibType14-NB-r13, sibType16-NB-r13,spare3, spare2, spare1} -- ASN1STOP

Table 38 represents description of SystemInformationBlockType1-NB filed.

TABLE 38 SystemInformationBlockType1-NB Field DescriptionsattachWithoutPDN-Connectivity If present, the field indicates thatattach without PDN connectivity as specified in TS 24.301 [35] issupported for this PLMN. CellBarred Barred means the cell is barred, asdefined in TS 36.304 [4]. cellIdentity Indicates the cell identity.cellReservedForOperatorUse As defined in TS 36.304 [4].cellSelectionInfo Cell selection information as specified in TS 36.304[4]. downlinkBitmap NB-IoT downlink subframe configuration for downlinktransmission. If the bitmap is not present, the UE shall assume that allsubframes are valid (except for subframes carryingNPSS/NSSS/NPBCH/SIB1-NB) as specified in TS 36.213[23].eutraControlRegionSize Indicates the control region size of the E-UTRAcell for the in-band operation mode. Unit is in number of OFDM symbols.freqBandIndicator A list of as defined in TS 36.101 [42, Table 6.2.4-1]for the frequency band in freqBandIndicator. freqBandInfo A list ofadditionalPmax and additionalSpectrumEmission values as defined in TS36.101 [42, Table 6.2.4-1] for the frequency band infreqBandInfofreqBandIndicator. hyperSFN-MSB Indicates the 8 mostsignificant bits of hyper-SFN. Together with hyperSFN-LSB in MIB-NB, thecomplete hyper-SFN is built up. hyper-SFN is incremented by one when theSFN wraps around. intraFreqReselection Used to control cell reselectionto intra-frequency cells when the highest ranked cell is barred, ortreated as barred by the UE, as specified in TS 36.304 [4].multiBandInfoList A list of additional frequency band indicators,additionalPmax and additionalSpectrumEmission values, as defined in TS36.101 [42, Table 5.5-1]. If the UE supports the frequency band in thefreqBandIndicator IE it shall apply that frequency band. Otherwise, theUE shall apply the first listed band which it supports in themultiBandInfoList IE. nrs-CRS-PowerOffset NRS power offset between NRSand E-UTRA CRS. Unit in dB. Default value of 0. plmn-IdentityList Listof PLMN identities. The first listed PLMN-Identity is the primary PLMN.p-Max Value applicable for the cell. If absent, the UE applies themaximum power according to the UE capability. q-QualMin Parameter“Q_(qualmin)” in TS 36.304 [4]. q-RxLevMin Parameter Q_(rxlevmin) in TS36.304 [4]. Actual value Q_(rxlevmin) = IE value * 2 [dB].schedulingInfoList Indicates additional scheduling information of SImessages. si-Periodicity Periodicity of the SI-message in radio frames,such that rf256 denotes 256 radio frames, rf512 denotes 512 radioframes, and so on. si-RadioFrameOffset Offset in number of radio framesto calculate the start of the SI window. If the field is absent, nooffset is applied. si-RepetitionPattern Indicates the starting radioframes within the SI window used for SI message transmission. Valueevery2ndRF corresponds to every second radio frame, value every4thRFcorresponds to every fourth radio frame and so on starting from thefirst radio frame of the SI window used for SI transmission. si-TB Thisfield indicates the transport block size in number of bits used tobroadcast the SI message. si-WindowLength Common SI scheduling windowfor all SIs. Unit in milliseconds, where ms160 denotes 160 milliseconds,ms320 denotes 320 milliseconds, and so on. sib-MappingInfo List of theSIBs mapped to this SystemInformation message. There is no mappinginformation of SIB2; it is always present in the first SystemInformationmessage listed in the schedulingInfoList list. systemInfoValueTagListIndicates SI message specific value tags. It includes the same number ofentries, and listed in the same order, as in SchedulingInfoList.systemInfoValueTagSI SI message specific value tag as specified inClause 5.2.1.3. Common for all SIBs within the SI message other thanSIB14. trackingAreaCode A trackingAreaCode that is common for all thePLMNs listed.

TABLE 39 Conditional presence Explanation inband The field is mandatorypresent if IE operationModeInfo in MIB-NB is set to inband-SamePCI orinband-DifferentPCI. Otherwise the field is not present. inband- Thefield is mandatory present, if IE operationModeInfo in SamePCI MIB-NB isset to inband-SamePCI. Otherwise the field is not present.

Machine Type Communication (MTC)

MTC has been mainly designed to use LTE for machine-to-machine (M2M) orInternet of things (IoT). In general, such an application requires notthat much throughput (in most case it needs very low throughput). Thekey requirements of M2M communications include cost reduction, reducedpower consumption, enhanced coverage, etc.

To facilitate MTC, long-term evolution (LTE) Release 12 has introducedsome initial features, such as new low-cost user equipment (UE)category, power saving mode (PSM), and UE assistance information forevolved NodeB (eNB) parameter tuning. The new low-cost UE categoryintroduced in LTE Release 12 is called as Category 0. In order to reducethe baseband and RF complexity of the UE, the Category 0 defines reducedpeak data rate (e.g. 1 Mbps), half duplex operation with relaxed radiofrequency (RF) requirements, and a single receive antenna. The PSMallows the UE to greatly reduce power consumption for applications withdelay-tolerant mobile-originated (MO) traffic in order to achieve yearsof battery lifetime.

It is obvious to those skilled in the art that the operations of theUE/base station described in the present disclosure can be applied tothe LTE MTC.

Before describing a method for transmitting and receiving SIB1-NB in theTDD NB-IoT system proposed in the present disclosure, abbreviations anddefinition of terms to be described later are summarized.

Abbreviation

MIB-NB: masterinformationblock-narrowband

SIB1-NB: systeminformationblock1-narrowband

CRS: cell specific reference signal or common reference signal

ARFCN: absolute radio-frequency channel number

PRB: physical resource block

PRG: precoding resource block group

PCI: physical cell identifier

N/A: non-applicable

EARFCN: E-UTRA absolute radio frequency channel number

RRM: radio resource management

RSRP: reference signal received power

RSRQ: reference signal received quality

TBS: transport block size

TDD/FDD: time division duplex/frequency division duplex

Definition

NB-IoT: NB-IoT enables access to a network service through an E-UTRAusing a channel bandwidth limited to 200 kHz.

NB-IoT inband operation: NB-IoT operates as inband when using resourceblock(s) within a normal E-UTRA carrier.

NB-IoT guard band operation: NB-IoT operates as a guard band when usingresource block(s) that is not used within a guard band of an E-UTRAcarrier.

NB-IoT standalone operation: NB-IoT operates as standalone when usingits own spectrum. For example, a spectrum used by a current GERAN systeminstead of one or more GSM carriers and a scattered spectrum forpotential IoT deployment.

Anchor carrier: In NB-IoT, a carrier on which a UE assumes thatNPSS/NSSS/NPBCH/SIB-NB is transmitted for FDD, or NPSS/NSSS/NPBCH istransmitted for TDD.

Non-anchor carrier: In NB-IoT, a carrier on which a UE does not assumethat NPSS/NSSS/NPBCH/SIB-NB is transmitted for FDD, or NPSS/NSSS/NPBCHis transmitted for TDD.

Channel raster: a minimum unit by which a UE reads a resource. In caseof the LTE system, a channel raster has a value of 100 kHz.

Further, “/” described in the present disclosure may be interpreted as“and/or”, and “A and/or B” may be interpreted as the same meaning as“including at least one of A or (and/or) B”.

MTC physical downlink control channel (MPDCCH) is a MTC physicaldownlink control channel based on EPDCCH. Thus, in the same manner asthe EPDCCH, the MPDCCH estimates a channel based on a demodulationreference signal (DMRS) and performs MPDCCH demodulation using theestimated channel.

An LTE-MTC UE can perform time/frequency interpolation in the samemanner as the LTE UE, in order to enhance channel estimation capability.However, there may occur the case where it is impossible to perform thetime/frequency interpolation on a reference signal for MPDCCHdemodulation in terms of the channel estimation capability due to thefollowing signal characteristics.

Characteristics of MPDCCH Affecting MPDCCH Channel Estimation

-   -   A DMRS of MPDCCH is transmitted only for a physical resource        block (PRB) used for a transmission of MPDCCH.    -   Supporting MPDCCH formats supporting various enhanced control        channel element (ECCE) aggregation levels.    -   A MPDCCH format supported in LTE-MTC occupies 1/2/4 PRB: four        ECCEs may exist within one PRB. Thus, if a MPDCCH format where        AL≤4 performs localized transmission, the corresponding MPDCCH        is transmitted in one PRB, and a DMRS for MPDCCH is transmitted        only in the corresponding PRB. That is, a DMRS for the UE is not        transmitted in PRBs other than the corresponding PRB.    -   Supporting multiplexing of MPDCCH and PDSCH between the same or        different UEs within the same subframe (MPDCCH subframe)    -   The UE performs blind decoding (BD) for various MPDCCH formats        supported.

Due to the signal characteristics of the MPDCCH, PRB bundling is notsupported within an MPDCCH subframe. The PRB bundling refers to a methodfor allowing frequency interpolation to be performed between PRBs whenthe UE estimates channel, by applying the same precoding to differentPRBs.

In this instance, a group of PRBs to which the same precoding is appliedis called a precoding RB group (PRG).

Semi-Persistent Scheduling (SPS)

Semi-persistent scheduling (SPS) is a scheduling scheme in whichresources are allocated to a specific UE so as to be continuouslymaintained for a specific time duration.

When a predetermined amount of data is transmitted for a specific timelike Voice over Internet Protocol (VoIP), it is not necessary totransmit control information every data transmission interval forresource allocation, so the waste of control information can be reducedby using the SPS scheme. In the so-called SPS method, a time resourcedomain in which resources can be allocated to the UE is preferentiallyallocated.

In this instance, in the semi-persistent allocation method, the timeresource domain region allocated to the specific UE may be configured tohave periodicity. Then, the allocation of time-frequency resources iscompleted by allocating a frequency resource domain, if necessary ordesired. The allocation of the frequency resource domain as above may bereferred to as so-called activation. If the semi-persistent allocationmethod is used, repeated resource allocation need not be performed sincethe resource allocation is maintained during a predetermined period byone signaling, thereby reducing signaling overhead.

Thereafter, if resource allocation for the UE is no longer needed,signaling for releasing frequency resource allocation may be transmittedfrom the base station to the UE. Releasing the allocation of thefrequency resource domain as above may be referred to as deactivation.

In the current LTE, for the SPS for uplink and/or downlink, the UE ispreferentially informed in which subframes the SPS is to betransmitted/received via radio resource control (RRC) signaling. Thatis, the time resources are first designated among the time-frequencyresources allocated for the SPS via RRC signaling. In order to notifythe subframe which can be used, for example, a periodicity and an offsetof the subframe may be notified. However, since the UE is allocated onlythe time resource domain via RRC signaling, even if the UE has receivedthe RRC signaling, the UE does not immediately performtransmission/reception by the SPS, and completes the allocation oftime-frequency resources by allocating the frequency resource domain, ifnecessary. The allocation of the frequency resource domain as above maybe referred to as activation, and releasing the allocation of thefrequency resource domain as above may be referred to as deactivation.

Thus, after receiving PDCCH indicating activation, the UE allocates thefrequency resources according to RB allocation information included inthe received PDCCH, and applies modulation and a code rate depending onModulation and Coding Scheme (MCS) information to starttransmission/reception according to the subframe periodicity and offsetallocated via the RRC signaling.

Then, the UE stops transmission/reception when receiving the PDCCHindicating the deactivation from the base station. If the UE receives aPDCCH indicating activation or reactivation after stopping transmissionand reception, the UE resumes again the transmission and reception withthe subframe periodicity and offset allocated via RRC signaling using RBallocation or MCS designated by the PDCCH. That is, the allocation oftime resources is performed via RRC signaling, but the transmission andreception of the actual signal may be performed after receiving thePDCCH indicating the activation and reactivation of SPS, and theinterruption of the signal transmission/reception is performed afterreceiving the PDCCH indicating the deactivation of SPS.

Specifically, when SPS is enabled by RRC, the following information maybe provided:

-   -   SPS C-RNTI    -   uplink SPS interval semiPersistSchedIntervalUL and the number of        empty transmissions before implicit release, if SPS is enabled        for the uplink    -   whether twoIntervalsConfig is enabled or disabled for uplink,        only for TDD    -   downlink SPS interval semiPersistSchedIntervalDL and the number        of configured HARQ processes for SPS, if SPS is enabled for the        downlink,

Unlike this, if SPS is disabled by the RRC, the corresponding configuredgrant or configured assignment shall be discarded.

Further, the SPS is supported on the SpCell only and is not supportedfor RN communication with the E-UTRAN in combination with an RN subframeconfiguration.

In relation to the downlink SPS, after a semi-persistent downlinkassignment is configured, the MAC entity shall consider sequentiallythat the N-th assignment occurs in the subframe, as the followingEquation 21.

In relation to the downlink SPS, after a semi-persistent downlinkassignment is configured, the MAC entity shall consider sequentiallythat the N-th assignment occurs in the subframe, as the followingEquation 21.

(10*SFN+subframe)=[(10*SFNstart time+subframestarttime)+N*semiPersistSchedIntervalDL]modulo 10240  [Equation 21]

In Equation 21, SFNstart time and subframestart time denote a SFN and asubframe, respectively, at the time the configured downlink assignmentwas (re-)initialized. For BL UEs or UEs in enhanced coverage, theSFNstart time and the subframestart time may refer to a SFN and asubframe of the first transmission of PDSCH where configured downlinkassignment was (re-)initialized.

In contrast, in relation to the uplink SPS, after the semi-persistentuplink assignment is configured, the MAC entity shall considersequentially that the N-th grant occurs in a subframe, as the followingEquation 22.

(10*SFN+subframe)=[(10*SFNstart time+subframestarttime)+N*semiPersistSchedIntervalUL+Subframe_Offset*N modulo 2)]modulo10240  [Equation 22]

In Equation 22, SFNstart time and subframestart time denote a SFN and asubframe, respectively, at the time the configured uplink grant was(re-)initialized. For BL UEs or UEs in enhanced coverage, the SFNstarttime and the subframestart time may refer to a SFN and a subframe of thefirst transmission of PDSCH where configured uplink grant was (re-)initialized.

Table 40 below represents an example of an RRC message (SPS-Config) forspecifying the above-described SPS configuration.

TABLE 40 --ANS1START MasterInformationBlock-MB ::= SEQUENCE { systemFrameNumber-MSB-r13  BIT STRING (SIZE (4)),  hyperSFN-LSB-r13 BIT STRING (SIZE (2)),  schedulingInfoSBJ-r13  INTEGER (0..15), systemInfoValueTag-r13  INTEGER (0..31),  ab-Enabled-r13  BOOLEAN, operationModeInfo-r13  CHOICE {   inband-SamePCl-r13  Inband-SamePCl-NB-r13,   inband-DifferentPCl-r13  Inband-DifferentPCl-NB-r13,   guardband-r13   Guardband-NB-r13,  standalone-r13   Standalone-NB-r13  },  spare   BIT STRING (SIZE (11))} ChannelRasterOffset-NB-r13 ::= ENUMERATED {khz-7dot5, khz-3dot5,khz2dot3, khz7dot5} Guardband-NB-r13 ::= SEQUENCE {  rasterOffset-r13 ChannelMasterOffset-NB-r13.  spare   BIT STRING (SIZE (3)) }Inband-SamePCl-NB-r13 ::= SEQUENCE {  entra-CRS-SequenceInfo-r13 INTEGER (0..31) } Inband-DifferentPCl-NB-r13 ::= SEQUENCE { entra-NumCRS-Ports-r13  ENUMERATED (same, four),  rasterOffset-r13 ChannelRasterOffset-NB-r13.  spare   BIT STRING (SIZE (2)) }Standalone-NB-r13 ::= SEQUENCE {  spare   BIT STRING (SIZE (5)) }--ASN1STOP

PDCCH/EPDCCH/MPDCCH Validation for Semi-Persistent Scheduling

A UE may validate PDCCH including an SPS indication if all the followingconditions are met. First, CRC parity bits added for a PDCCH payloadshould be scrambled with SPS C-RNTI, and second, a new data indicator(NDI) field should be set to zero. In case of DCI formats 2, 2A, 2B, 2Cand 2D, the new data indicator field refers to the one for the enabledtransport block.

Further, the UE may validate EPDCCH including the SPS indication if allthe following conditions are met. First, CRC parity bits added for anEPDCCH payload should be scrambled with SPS C-RNTI, and second, the newdata indicator (NDI) field should be set to zero. In case of DCI formats2, 2A, 2B, 2C, and 2D, the new data indicator field refers to the onefor the enabled transport block.

Further, the UE may validate MPDCCH including the SPS indication if allthe following conditions are met. First, CRC parity bits added for anMPDCCH payload should be scrambled with SPS C-RNTI, and second, the newdata indicator (NDI) field should be set to zero.

When each field used for a DCI format is configured according to Table39 or Tables 40, 41 42 below, the validation is completed. If thevalidation is completed, the UE recognizes the received DCI informationas valid SPS activation or deactivation (or release). On the other hand,if the validation is not completed, the UE recognizes that non-matchingCRC is included in the received DCI format.

Table 41 represents fields for PDCCH/EPDCCH validation indicating SPSactivation.

TABLE 41 DCI DCI format DCI format format 0 1/1A 2/2A/2B/2C/2D TPCcommand set to N/A N/A for scheduled ‘00’ PUSCH Cyclic shift set to N/AN/A DM RS ‘000’ Modulation and MSB is N/A N/A coding scheme set to ‘0’and redundancy version HARQ process N/A FDD: set to ‘000’ FDD: set to‘000’ number TDD: set to ‘0000’ TDD: set to ‘0000’ Modulation and N/AMSB is set to ‘0’ For the enabled coding scheme transport block: MSB isset to ‘0’ Redundancy N/A set to ‘00’ For the enabled version transportblock: set to ‘00’

Table 42 represents fields for PDCCH/EPDCCH validation indicating SPSdeactivation (or release).

TABLE 42 DCT format 0 DCI format 1A TPC command for set to ‘00’ N/Ascheduled PUSCH Cyclic shift DM RS set to ‘000’ N/A Modulation and setto ‘11111’ N/A coding scheme and redundancy version Resource block Setto all ‘1’s N/A assignment and hopping resource allocation HARQ processN/A FDD: set to ‘000’ number TDD: set to ‘0000’ Modulation and N/A setto ‘11111’ coding scheme Redundancy version N/A set to ‘00’

Table 43 represents fields for MPDCCH validation indicating SPSactivation.

TABLE 43 DCI format 6-0A DCI format 6-1A HARQ process number set to‘000’ FDD: set to ‘000’ TDD: set to ‘0000’ Redundancy version set to‘00’ set to ‘00’ TPC command for set to ‘00’ N/A scheduled PUSCH TPCcommand N/A set to ‘00’ for scheduled PUCCH

Table 44 represents fields for MPDCCH validation indicating SPSdeactivation (or release).

TABLE 44 DCI format 6-0A DCI format 6-1A HARQ process number set to‘000’ FDD: set to ‘000’ TDD: set to ‘0000’ Redundancy version set to‘00’ set to ‘00’ Repetition number set to ‘00’ set to ‘00’ Modulationand coding scheme set to ‘1111’ set to ‘1111’ TPC command for set to‘00’ N/A scheduled PUSCH Resource block assignment Set to all ‘1’s Setto all‘1’s

If the DCI format indicates SPS downlink scheduling activation, valuesof TPC command for the PUCCH field may be used as indexes representingfour PUCCH resource values configured by higher layers.

Table 45 represents PUCCH resource values for downlink SPS.

TABLE 45 Value of ‘TPC command for PUCCH’ n_(PUCCH) ^((1, p)) ‘00’ Thefirst PUCCH resource value configured by the higher layers ‘01’ Thesecond PUCCH resource value configured by the higher layers ‘10’ Thethird PUCCH resource value configured by the higher layers ‘11’ Thefourth PUCCH resource value configured by the higher layers

Downlink Control Channel Related Procedure in NB-IoT

A procedure related to narrowband physical downlink control channel(NPDCCH) used for NB-IoT will be described.

A UE shall monitor NPDCCH candidates (i.e., a set of NPDCCH candidates)as configured by higher layer signalling for control information, wheremonitoring may imply attempting to decode each of the NPDCCHs in the setaccording to all the monitored DCI formats. The set of NPDCCH candidatesto monitor are defined in terms of NPDCCH search spaces. In this case,the UE may perform monitoring using identifiers (e.g., C-RNTI, P-RNTI,SC-RNTI, G-RNTI) corresponding to the respective NPDCCH search spaces.

In this case, the UE shall monitor one or more of a) Type1-NPDCCH commonsearch space, b) Type2-NPDCCH common search space, and c) NPDCCHUE-specific search space. In this instance, a UE is not required tosimultaneously monitor a NPDCCH UE-specific search space and aType1-NPDCCH common search space. A UE is not required to simultaneouslymonitor a NPDCCH UE-specific search space and a Type2-NPDCCH commonsearch space. A UE is not required to simultaneously monitor aType-1-NPDCCH common search space and a Type2-NPDCCH common searchspace.

An NPDCCH search space at an aggregation level and a repetition level isdefined by a set of NPDCCH candidates, where each NPDCCH candidate isrepeated in a set of R consecutive NB-IoT downlink subframes excludingsubframes used for transmission of system information (SI) messagesstarting with subframe k.

For the NPDCCH UE-specific search space, the aggregation and repetitionlevels defining the corresponding search spaces and the correspondingNPDCCH candidates being monitored are listed in Table 46 by substitutingthe value of R_(max) with the higher layer configured parameteral-Repetition-USS.

TABLE 46 NCCE indices of monitored NPDCCH candidates R_(max) R L′ = 1 L′= 2 1 1 {0}, {1} {0, 1} 2 1 {0}, {1} {0, 1} 2 — {0, 1} 4 1 — {0, 1} 2 —{0, 1} 4 — {0, 1} > = 8 R_(max)/8 — {0, 1} R_(max)/4 — {0, 1} R_(max)/2— {0, 1} R_(max) — {0, 1} Note 1 {x}, {y} denote NPDCCH Format 0candidate with NCCE index ‘x’ and NPDCCH Format 0 candidate with NCCEindex ‘y’. Note 2 {x, y} denotes NPDCCH Format 1 candidate correspondingto NCCE indexes ‘x’ and ‘y’.

For the Type1-NPDCCH common search space, the aggregation and repetitionlevels defining the corresponding search spaces and the correspondingNPDCCH candidates being monitored are listed in Table 47 by substitutingthe value of R_(max) with the higher layer configured parameteral-Repetition-CSS-Paging.

TABLE 47 NCCE indices of monitored NPDCCH candidates R_(max) R L′ = 1 L′= 2    1 1 — {0, 1}    2 1, 2 — {0, 1}    4 1, 2, 4 — {0, 1}    4 1, 2,4, 8 — {0, 1}   16 1, 2, 4, 8, 16 — {0, 1}   32 1, 2, 4, 8, 16, 32 — {0,1}   64 1, 2, 4, 8, 16, 32, 64 — {0, 1}  128 1, 2, 4, 8, 16, 32, 64, 128— {0, 1}  256 1, 4, 8, 16, 32, 64, 128, 256 — {0, 1}  512 1, 4, 16, 32,64, 128, 256, 512 — {0, 1} 1024 1, 8, 32, 64, 128, 256, 512, 1024 — {0,1} 2048 1, 8, 64, 128, 256, 512, 1024, 2048 — {0, 1} Note 1{x}, {y}denote NPDCCH Format 0 candidate with NCCE index ‘x’ and NPDCCH Format 0candidate with NCCE index ‘y’ . Note 2 {x, y} denotes NPDCCH Format 1candidate corresponding to NCCE indexes ‘x’ and ‘y’ .

For the Type2-NPDCCH common search space, the aggregation and repetitionlevels defining the corresponding search spaces and the correspondingNPDCCH candidates being monitored are listed in Table 48 by substitutingthe value of R_(max) with the higher layer configured parameternpdcch-MaxNumRepetitions-RA.

TABLE 48 NCCE indices of monitored NPDCCH candidates R_(max) R L′ = 1 L′= 2 1 1 — {0, 1} 2 1 — {0, 1} 2 — {0, 1} 4 1 — {0, 1} 2 — {0, 1} 4 — {0,1} > = 8 R_(max)/8 — {0, 1} R_(max)/4 — {0, 1} R_(max)/2 — {0, 1}R_(max) — {0, 1} Note 1 {x}, {y} denote NPDCCH Format 0 candidate withNCCE index ‘x’ and NPDCCH Format 0 candidate with NCCE index ‘y’. Note 2{x, y} denotes NPDCCH Format 1 candidate corresponding to NCCE indexes‘x’ and ‘y’.

The locations of starting subframe k are given by k=kb, where kb is theb-th consecutive NB-IoT downlink subframe from subframe k0, b=u*R, andu=0, 1, . . . , (R_(max)/R)−1. Further, the subframe k0 refers to asubframe satisfying the following Equation 23.

(10n _(c) +└n _(s)/2┘)mod T=α _(offset) ·T, where T=R _(max)·G  [Equation 23]

For NPDCCH UE-specific search space, G in Equation 23 is given by thehigher layer parameter nPDCCH-startSF-UESS, and α_(offset) is given bythe higher layer parameter nPDCCH-startSFoffset-UESS. For NPDCCHType2-NPDCCH common search space, G in Equation 23 is given by thehigher layer parameter nPDCCH-startSF-Type2CSS, and α_(offset) is givenby the higher layer parameter nPDCCH-startSFoffset-Type2CSS. ForType1-NPDCCH common search space, k=k0 and is determined from locationsof NB-IoT paging opportunity subframes.

If the UE is configured by high layers with a PRB for monitoring ofNPDCCH UE-specific search space, the UE shall monitor the NPDCCHUE-specific search space on the higher layer configured PRB. In thiscase, the UE is not expected to receive NPSS, NSSS and NPBCH on thehigher layer configured PRB. On the other hand, if the PRB is notconfigured by high layers, the UE shall monitor the NPDCCH UE-specificsearch space on the same PRB on which NPSS/NSSS/NPBCH are detected.

If a NB-IoT UE detects NPDCCH with DCI Format N0 ending in subframe n,and if the corresponding NPUSCH format 1 transmission starts fromsubframe n+k, the UE is not required to monitor NPDCCH in any subframestarting from subframe n+1 to subframe n+k−1.

If a NB-IoT UE detects NPDCCH with DCI Format N1 or DCI format N2 endingin subframe n, and if the corresponding NPDSCH transmission starts fromsubframe n+k, the UE is not required to monitor NPDCCH in any subframestarting from subframe n+1 to subframe n+k−1.

If a NB-IoT UE detects NPDCCH with DCI Format N1 ending in subframe n,and if the corresponding NPUSCH format 2 transmission starts fromsubframe n+k, the UE is not required to monitor NPDCCH in any subframestarting from subframe n+1 to subframe n+k−1.

If a NB-IoT UE detects NPDCCH with DCI Format N1 for “PDCCH order”ending in subframe n, and if the corresponding NPRACH transmissionstarts from subframe n+k, the UE is not required to monitor NPDCCH inany subframe starting from subframe n+1 to subframe n+k−1.

If a NB-IoT UE has a NPUSCH transmission ending in subframe n, the UE isnot required to monitor NPDCCH in any subframe starting from subframen+1 to subframe n+3.

A NB-IoT UE is not required to monitor NPDCCH candidates of an NPDCCHsearch space, if an NPDCCH candidate of the NPDCCH search space ends insubframe n, and if the UE is configured to monitor NPDCCH candidates ofanother NPDCCH search space starting before subframe n+5.

Regarding NPDCCH starting position, the starting OFDM symbol for NPDCCHis given by index l_(NPDCCHStart) in the first slot in a subframe k. Inthis instance, if higher layer parameter operarionModeInfo indicates‘00’, or ‘01’, the index l_(NPDCCHStart) is given by the higher layerparameter eutaControlRegionSize. Alternatively, if higher layerparameter operarionModeInfo indicates ‘10’, or ‘11’, i_(NPDCCHStart)=0.

NPDCCH Validation for Semi-Persistent Scheduling (SPS)

A UE may decide a semi-persistent scheduling assignment NPDCCH is validonly if all the following conditions are met.

-   -   the CRC parity bits obtained for the NPDCCH payload shall be        scrambled with the semi-persistent scheduling C-RNTI.    -   the new data indicator field shall be set to ‘0’.

If all the fields for DCI format N0 used are configured according to thefollowing Table 50 or 51, the validity of NPDCCH can be validated.

TABLE 50 DCI format N0 HARQ process number (present if UE is set to ‘0’configured with 2 uplink HARQ processes) Redundancy version set to ‘0’Modulation and coding scheme set to ‘0000’ Resource assignment set to‘000’

TABLE 51 DCI format N0 HARQ process number (present if UE is set to ‘0’configured with 2 uplink HARQ processes) Redundancy version set to ‘0’Repetition number set to ‘000’ Modulation and coding scheme set to‘1111’ Subcarrier indication set to all ‘1’s

If the validity of NPDCCH is validated, the UE shall consider the NPDCCHas a valid semi-persistent activation or release based on the receivedDCI information.

If the validity of NPDCCH is not validated, the UE shall consider thereceived DCI information as having been received with a non-matchingCRC.

DCI Format

DCI transmits downlink or uplink scheduling information for one cell andone RNTI. The RNTI is implicitly encoded in the CRC.

As a DCI format related to NB-IoT, DCI format N0, DCI format N1, and DCIformat N2 may be considered.

First, DCI format N0 is used for the scheduling of NPUSCH in one UL celland may transmit the following information.

-   -   Flag for differentiation of format N0 and format N1 (e.g., 1        bit), where value 0 may indicate format N0, and value 1 may        indicate format N1    -   Subcarrier indication (e.g., 6 bits)    -   Resource assignment (e.g., 3 bits)    -   Scheduling delay (e.g., 2 bits)    -   Modulation and coding Scheme (e.g., 4 bits)    -   Redundancy version (e.g., 1 bit)    -   Repetition number (e.g., 3 bits)    -   New data indicator (e.g., 1 bit)    -   DCI subframe repetition number (e.g., 2 bits)

Next, DCI format N1 is used for the scheduling of one NPDSCH codeword inone cell and a random access procedure initiated by a NPDCCH order. TheDCI corresponding to the NPDCCH order is carried by NPDCCH.

The DCI format N1 may transmit the following information.

-   -   Flag for differentiation of format N0 and format N1 (e.g., 1        bit), where value 0 may indicate format N0, and value 1 may        indicate format N1.

Format N1 is used for a random access procedure initiated by a NPDCCHorder, only if NPDCCH order indicator is set to ‘1’, format N1 cyclicredundancy check (CRC) is scrambled with C-RNTI, and all the remainingfields are set as follows.

-   -   Starting number of NPRACH repetitions (e.g., 2 bits)    -   Subcarrier indication of NPRACH (e.g., 6 bits)    -   All the remaining bits in format N1 are set to ‘1’

Otherwise, the following remaining information is transmitted.

-   -   Scheduling delay (e.g., 3 bits)    -   Resource assignment (e.g., 3 bits)    -   Modulation and coding scheme (e.g., 4 bits)    -   Repetition number (e.g., 4 bits)    -   New data indicator (e.g., 1 bit)    -   HARQ-ACK resource (e.g., 4 bits)    -   DCI subframe repetition number (e.g., 2 bits)

When the format N1 CRC is scrambled with a RA-RNTI, the followinginformation (i.e., fields) among the above information (i.e., fields)are reserved.

-   -   New data indicator    -   HARQ-ACK resource

If the number of information bits in format N1 is less than the numberof information bits in format N0, zeros shall be appended to format N1until the payload size in format N1 is equal to the payload size informat N0.

Next, DCI format N2 is used for for paging and direct indication and maytransmit the following information.

-   -   Flag for differentiation of paging and direct indication (e.g.,        1 bit), where value 0 may indicate direct indication, and value        1 may indicate paging.

If the value of flag is zero (Flag=0), DCI format N2 includes (ortransmits) direct indication information (e.g., 8 bits) and reservedinformation bits that are configured so that the size is equal to thesize of format N2 with Flag=1.

On the other hand, if the value of flag is 1 (Flag=1), DCI format N2includes (or transmits) resource assignment (e.g., 3 bits), modulationand coding scheme (e.g., 4 bits), repetition number (e.g., 4 bits), andDCI subframe repetition number (e.g., 3 bits).

Resource Allocation for Uplink Transmission with Configured Grant

When PUSCH resource allocation is semi-statically configured by higherlayer parameter ConfiguredGrantConfig in BWP information element, andPUSCH transmission corresponding to a configured grant is triggered, thefollowing higher layer parameters are applied in the PUSCH transmission:

-   -   For Type 1 PUSCH transmission with a configured grant, the        following parameters are given in ConfiguredGrantConfig.    -   The higher layer parameter timeDomainAllocation value m provides        a row index m+1 pointing to an allocated table, and the        allocated table indicates a start symbol, a length, and a        combination of PUSCH mapping types. The table selection follows        rules for the UE-specific search space defined in clause        6.1.2.1.1 of TS 38.214.    -   Frequency domain resource allocation is determined, for a given        resource allocation type indicated by resourceAllocation, by the        higher layer parameter frequencyDomainAllocation according to        the procedure of clause 6.1.2.2 of TS 38.214.    -   I_(MCS) is provided by higher layer parameter mcsAndTBS.    -   Number of DM-RS CDM groups, DM-RS ports, SRS resource        indication, and DM-RS sequence initialization are determined as        in Clause 7.3.1.1 of TS 38.212. The antenna port value, the bit        value for DM-RS sequence initialization, precoding information        and number of layers, the SRS resource indicator are provided by        antennaPort, dmrs-SeqInitialization, precodingAndNumberOfLayers        and srs-ResourceIndicator, respectively.    -   When frequency hopping is enabled, the frequency offset between        two frequency hops can be configured by higher layer parameter        frequencyHoppingOffset.    -   For Type 2 PUSCH transmission with a configured grant: the        resource allocation follows the higher layer configuration        according to [10, TS 38.321], and UL grant received on the        downlink control information (DCI).

The UE does not transmit anything on the resources configured byConfiguredGrantConfig, if the higher layers do not deliver a transportblock to transmit on the resources allocated for uplink transmissionwithout grant.

A set of allowed periodicities P are defined in [12, TS 38.331].

Transport Block repetition for uplink transmission with a configuredgrant

The higher layer configuration parameters repK and repK-RV define Krepetitions to be applied to a transmitted transport block and aredundancy version (RV) pattern to be applied to the repetition. For ann-th transmission occasion among K repetitions, where n=1, 2, . . . , K,the corresponding transmission is associated with (mod(n−1,4)+1)th valuein the configured RV sequence. The initial transmission of a transportblock may start in the following cases.

-   -   the first transmission occasion of the K repetitions if the        configured RV sequence is {0,2,3,1},    -   any one of the transmission occasions of the K repetitions that        are associated with RV=0 if the configured RV sequence is        {0,3,0,3},    -   any one of the transmission occasions of the K repetitions if        the configured RV sequence is {0,0,0,0} (except the last        transmission occasion when K=8).

For any RV sequence, the repetitions shall be terminated whentransmitting K repetitions, or at the last transmission occasion amongthe K repetitions within the period P, or when the UL grant forscheduling the same TB is received within the period P, whichever isreached first.

The UE is not expected to be configured with the time duration for thetransmission of K repetitions larger than the time duration derived bythe periodicity P.

For both Type 1 and Type 2 PUSCH transmissions, when the UE isconfigured with repK>1, the UE shall repeat the TB across the repKconsecutive slots applying the same symbol allocation in each slot. If aUE procedure for determining the slot configuration defined in clause11.1 of TS 38.213 determines a symbol of a slot allocated for PUSCH as adownlink symbol, a transmission in the corresponding slot is omitted fora multi-slot PUSCH transmission.

Uplink Power Control in NB-IoT

The uplink power control controls the transmit power of another uplinkphysical channel.

UE Behaviour for Uplink Power Control

The setting of the UE transmit power for a narrowband physical uplinkshared channel (NPUSCH) transmission is defined as follows. For FDD, theUE is capable of enhanced random access power control [12], and it isconfigured by higher layers, and for TDD, enhanced random access powercontrol shall be applied for a UE which started the random accessprocedure in the first or second configured NPRACH repetition level.

The UE transmit power P_(NPUSCH,c)(i) for NPUSCH transmission in NB-IoTUL slot i for the serving cell c is given as follows:

For NPUSCH (re)transmissions corresponding to the random access responsegrant if enhanced random access power control is not applied, and forall other NPUSCH transmissions in which the number of repetitions of theallocated NPUSCH RUs is greater than 2:

P _(NPUSCH,c)(i)=P _(CMAX,c)(i)  [Equation 24]

otherwise,

                                     [Equation  25]${P_{{NPUSCH},c}(j)} - {\min{\begin{Bmatrix}{{P_{{CMAX},c}(i)},} \\{{10{\log_{10}\left( {M_{{NPUSCH},c}(i)} \right)}} + {P_{{O\_{NPUSCH}},c}(j)} + {{\alpha_{s}(j)} \cdot {PL}_{c}}}\end{Bmatrix}\lbrack{dBm}\rbrack}}$

where, for the serving cell c

-   -   P_(CMAX,c)(i) is the configured UE transmit power defined in [6]        in NB-IoT UL slot i for the serving cell c.    -   P_(O_NPUSCH,c)(j) is a parameter composed of the sum of a        component P_(O_NOMINAL_PUSCH,c)(j) provided from higher layers        and a component P_(O_UE_NPUSCH,c)(j) provided from higher layers        for j=1 and for the serving cell c, where j∈{1,2}. For NPUSCH        (re)transmissions corresponding to a dynamic scheduled grant,        then j=1, for NPUSCH (re)transmissions corresponding to a random        access response grant, then j=2, P_(O_UE_NPUSCH,c)(2)=0. If        enhanced random access power control is not applied,        P_(O_NORMINAL_PUSCH,c)(2)=P_(O_PRE)+Δ_(PREAMBLE_Msg3), where the        parameter preambleInitialReceivedTargetPower [8] (P_(O_PRE)) and        Δ_(PREAMBLE_Msg3) are signalled from higher layers for serving        cell c. If enhanced random access power control is applied,

P_(O_NORMINAL_PUSCH,c)(2)=MSG3_RECEIVED_TARGET_POWER+Δ_(PREAMBLE,Msg3)  [Equation26]

For j=1, for NPUSCH format 2, α_(c)(j)=1; for NPUSCH format 1, α_(c)(j)is provided by higher layers for serving cell c. For j=2, (j)=1.

PL_(c) is the downlink path loss estimate calculated in the UE forserving cell c and PL_(c)=nrs-Power+nrs-PowerOffsetNonAnchor−NRSRP,where nrs-Power is provided by higher layers and subclause 16.2.2.2, andnrs-power-offsetNonAnchor is set to zero if it is not provided by higherlayers.

Power Headroom

If the UE transmits NPUSCH in NB-IoT UL slot i for serving cell c, powerheadroom is computed using the following.

$\begin{matrix}{\mspace{79mu}{{{{PH}\text{?}(i)} = {{P\text{?}(i)} - {\left\{ {{P\text{?}(1)} + {\text{?}{(1) \cdot {PL}}\text{?}}} \right\}\lbrack{dB}\rbrack}}}{\text{?}\text{indicates text missing or illegible when filed}}}} & \left\lbrack {{Equation}\mspace{14mu} 27} \right\rbrack\end{matrix}$

Where, P_(CMAX,c)(i), P_(O_NPUSCH,c)(l), α_(c)(l), and PL_(c) aredefined in subclause 16.2.1.1.1.

The power headroom shall be rounded down to the closest value in the set[PH1, PH2, PH3, PH4] dB as defined in [10], and the power headroom shallbe delivered by the physical layer to higher layers.

Embodiments of the Present Disclosure

The contents (3GPP system, frame structure, NB-IoT system, etc.)described above can be applied in combination to methods according tothe present disclosure to be described below, or can be supplemented toclarify technical features of methods described in the presentdisclosure.

Narrowband (NB)-LTE is a system for supporting low complexity and lowpower consumption with a system BW corresponding to 1 PRB of the LTEsystem. This may be mainly used as a communication method forimplementing internet of things (IoT) by supporting devices such asmachine-type communication (MTC) in a cellular system. By using, as OFDMparameters such as subcarrier spacing of the existing LTE, the sameparameters as LTE, there is an advantage in that 1 PRB is allocated tothe legacy LTE band for NB-LTE without additional band allocation,thereby enabling the frequency to be used efficiently. In case ofdownlink, a physical channel of NB-LTE is defined as NPSS/NSSS, NPBCH,NPDCCH/NEPDCCH, NPDSCH, etc., and N is added to distinguish from LTE.

In Legacy LTE and LTE eMTC, semi-persistent scheduling (SPS) has beenintroduced and used. First, the UE receives SPS configuration setupinformation via RRC signaling. Subsequently, if the UE receives SPSactivation DCI (with SPS-C-RNTI), the SPS operates using SPSconfiguration information received via RRC signaling, resourcescheduling information included in corresponding DCI, MCS information,etc. If the UE receives SPS release DCI (with SPS-C-RNTI), the SPS isreleased. Thereafter, if the UE receives again the SPS activation DCI(with SPS-C-RNTI), the SPS operates as described above. If the UEreceives the SPS release DCI (with SPS-C-RNTI) and then receives SPSconfiguration release information via RRC signaling, the correspondingUE cannot detect the SPS activation DCI until receiving the SPSconfiguration setup information again (because the UE does not know theSPS-C-RNTI value).

The phrase ‘monitoring a search space’ used in the present disclosuremeans a process of decoding an NPDCCH for a specific area according to aDCI format to be received through the search space and then scramblingthe corresponding CRC with a preset specific RNTI value to check whethera desired value is correct. In addition, since each UE in the NB-LTEsystem recognizes a single PRB as a respective carrier, it can be saidthat a PRB mentioned in the present disclosure has the same meaning as acarrier. DCI formats N0, N1, and N2 mentioned in the present disclosurerefer to DCI formats N0, N1, and N2 in the 3GPP TS 36.212[2] standard.

In addition, the above contents (3GPP system, frame structure, NB-IoTsystem, etc.) may be applied in combination with methods according tothe present disclosure described below, or may be supplemented toclarify technical features of methods described in the presentdisclosure.

FIG. 18 illustrates an example of an operation flow chart of a UEperforming an idle mode preconfigured UL resource transmission of one ormore physical channels/signals to which a method described in thepresent disclosure is applicable.

FIG. 18 illustrates merely an example for convenience of explanation,and does not limit the scope of the present disclosure.

FIG. 19 illustrates an example of an operation flow chart of a basestation performing an idle mode preconfigured UL resource transmissionof one or more physical channels/signals to which a method described inthe present disclosure is applicable.

FIG. 19 illustrates merely an example for convenience of explanation,and does not limit the scope of the present disclosure.

FIG. 20 illustrates an example of signalling between a UE and a basestation performing an idle mode preconfigured UL resourcetransmission/reception of one or more physical channels/signals to whicha method described in the present disclosure is applicable.

FIG. 20 illustrates merely an example for convenience of explanation,and does not limit the scope of the present disclosure.

FIG. 21 illustrates a block configuration diagram of a wirelesscommunication device to which methods described in the presentdisclosure are applicable.

For example, an operation of the base station and the UE in FIGS. 18 to20 and methods according to the present disclosure described below canbe performed by a base station 910 and a UE 920 described below.

Referring to FIG. 21, a wireless communication system includes a basestation 2110 and multiple UEs 2120 located in an area of the basestation. The base station 2110 may be represented by a transmitter, andthe UE 2120 may be represented by a receiver, or vice versa. The basestation 2110 and the UE 2120 respectively include processors 2111 and2121, memories 2114 and 2124, one or more Tx/Rx RF modules 2115 and2125, Tx processors 2112 and 2122, Rx processors 2113 and 2123, andantennas 2116 and 2126. The processors implement functions, processes,and/or methods mentioned above. More specifically, in DL (communicationfrom the base station to the UE), an upper layer packet from a corenetwork is provided to the processor 2111. The processor implementsfunctionality of the L2 layer. In the DL, the processor providesmultiplexing between a logical channel and a transport channel and radioresource allocation to the UE 2120 and is also responsible for signalingto the UE 2120. The transmit (Tx) processor 2112 implements varioussignal processing functions for the L1 layer (i.e., physical layer). Thesignal processing functions include coding and interleaving tofacilitate forward error correction (FEC) at the UE. The coded andmodulated symbols are split into parallel streams, and each stream ismapped to an OFDM subcarrier, multiplexed with a reference signal (RS)in time and/or frequency domain, and combined together using an InverseFast Fourier Transform (IFFT) to produce a physical channel carrying atime domain OFDMA symbol stream. The OFDMA stream is spatially precodedto produce multiple spatial streams. Each spatial stream may be providedto the different antenna 2116 via a separate Tx/Rx module (ortransceiver 2115). Each Tx/Rx module may modulate an RF carrier with arespective spatial stream for transmission. At the UE, each Tx/Rx module(or transceiver 2125) receives a signal through the respective antenna2126 of each Tx/Rx module. Each Tx/Rx module recovers informationmodulated onto an RF carrier and provides the information to the receive(Rx) processor 2123. The RX processor implements various signalprocessing functions of the Layer 1. The Rx processor may performspatial processing on the information to recover any spatial streamdestined for the UE. If multiple spatial streams are destined for theUE, they may be combined into a single OFDMA symbol stream by themultiple Rx processors. The Rx processor converts the OFDMA symbolstream from the time domain to the frequency domain using a Fast FourierTransform (FFT). The frequency domain signal includes a separate OFDMAsymbol stream for each subcarrier of the OFDM signal. The symbols oneach subcarrier and the reference signal are recovered and demodulatedby determining the most likely signal constellation points transmittedby the base station. These soft decisions may be based on channelestimation values. The soft decisions are decoded and de-interleaved torecover data and control signals that were originally transmitted by thebase station on the physical channel. The corresponding data and controlsignals are provided to the processor 2121.

UL (communication from the UE to the base station) is processed at thebase station 2110 in a manner similar to the description associated witha receiver function at the UE 2120. Each Tx/Rx module 2125 receives asignal through the respective antenna 2126. Each Tx/Rx module providesan RF carrier and information to the Rx processor 2123. The processor2121 may be associated with the memory 2124 that stores a program codeand data. The memory may be referred to as a computer readable medium.

First Embodiment: Feedback Channel Design for Preconfigured UL Resource(PUR)

The contents (3GPP system, frame structure, NB-IoT system, etc.)described above can be applied in combination to methods according tothe present disclosure to be described below, or can be supplemented toclarify technical features of methods described in the presentdisclosure.

In Rel.16 NB-IoT, the concept of a UE transmitting UL data to apreconfigured UL resource in an idle mode is discussed. To this end, abase station may indicate a preconfigured UL resource, to which the UEtransmits UL data, via SIB or RRC signaling when the UE is in the idlemode in which an Uplink TA is valid.

In this instance, the base station may configure the preconfigured ULresource to each UE in a dedicated resource type, or may configure thepreconfigured UL resource to a plurality of UEs in a shared resourcetype. In general, the dedicated resource type may define UL data thatcan make it possible to predict which UE, what time point, or how muchinformation to transmit. That is, the dedicated resource type has adisadvantage in that the UE shall always occupy UL resources from aresource utilization perspective, but it has an advantage of being ableto transmit UL data without contention (e.g., contention free) becausethe UE has its own dedicated resource. On the other hand, the sharedresource type may define UL data which cannot make it possible topredict which UE, what time point, and how much information. That is,the shared resource type may have a disadvantage in that the UE shallperform contention-based operation, but it is free from the resourceutilization perspective compared to the dedicated resource type. Forexample, it is because a longer period can be made or because there isno need to prepare all resources for a plurality of UEs that wish PUR).

1-1 Embodiment: Different Resources+ACK/NACK Multiplexing

First, a method for a base station to multiplex ACK/NACK of UEstransmitted from different PURs and transmit the same at once isdescribed. This method is described in detail below.

The base station may configure the PUR to the UE UE-specifically or CElevel-specifically or cell-specifically via higher layer signaling. Inthe following, a CE mode may also be included in the CE level, where theCE mode may be a value selected by the CE level or a value set by thebase station in the RRC connected mode. In this instance, if the basestation UE-specifically configures the PUR to the UEs, the PUR maybecome a dedicated resource type of PUR, and if the base stationconfigures the PUR to the UEs CE level-specifically orcell-specifically, the PUR may become a shared resource type of PUR.Additionally, the base station may also transmit search space (e.g.,legacy CSS type or new CSS for PUR) information, to which feedbackinformation (e.g., ACK/NACK) of respective PURs is transmitted, viahigher layer signaling. Characteristically, since the base stationconsiders multiplexing the ACK/NACK of respective PURs, the search spaceinformation to which the corresponding ACKs/NACKs are transmitted may beconfigured CE level-specifically or cell-specifically.

Thereafter, the UE receives/acquires PUR information configured by thebase station via higher layer signaling received from the base station,and the UE transmits uplink data to the corresponding PUR if uplink datato be transmitted is generated. In this instance, characteristically, ifthe dedicated resource type of PUR is considered,time/frequency/code/spatial resource for PUR transmission may bedifferently configured for each UE.

A method for a base station to multiplex ACK/NACK for the transmitted ULdata can be considered in various ways below.

As a first method for the base station to multiplex ACK/NACK, a methodfor the base station to transmit ACK/NACK information for a plurality ofUL data to one search space may be considered. More specifically, thebase station may be configured to indicate ACK/NACK by transmittingDCIs, that are different UE information and are distinguishable, to aplurality of (N)PDCCH candidates existing in a preconfigured searchspace. In this instance, a value that can be used as different UEinformation may be configured to use an RNTI value calculated based on atime/frequency/code/spatial resource location of a PUR transmitted byeach UE and/or a unique UE ID.

Further, a UE that has entered a connected mode in a corresponding cellmay be configured to use a C-RNTI value used in a previous connectedmode. Characteristically, in a PUR of the shared resource type, if RNTIis generated only with the time/frequency/code/spatial resource locationof a PUR, RNTI may all be calculated the same, so UE-specificinformation such as a unique UE ID may be considered essentially. Inthis instance, DCI indicating the corresponding ACK/NACK may not need toschedule the NPDSCH, and hence, a corresponding payload size may not belarger than a payload size of the legacy DCI (e.g., DCI format N0).Thus, the base station can send DCI, which is more than the existingsearch space, to the search space for the purpose of PUR feedback.

As another method for the base station to multiplex ACK/NACK, it may beconfigured such that an ACK/NACK mapping order is determined dependingon a UL data transmission time/frequency/code/spatial resource locationof a PUR configured by the base station (i.e., a relative locationbetween resources within the PUR or a location of a PRB/base stationtransmit antenna port resource within absolute time/system BW).Characteristically, in a PUR of the dedicated resource type, the basestation can configure a period of the corresponding PUR or a PUR window,starting subframe offset, a PRB index, a maximum TBS, etc., and caninform a UE in advance of information that ACK/NACK will be multiplexedwith other UEs using the same or similar period, and the correspondingACK/NACK multiplexing may exist in the form of a bitmap in the DCIfield. In this instance, it may be configured such that the order inwhich ACK/NACK of a specific UE is transmitted is determined using aperiod of a corresponding PUR, a starting subframe offset, a PRB index,and a maximum TBS. Characteristically, in this case, UEs that expect thecorresponding ACK/NACK multiplexing may be configured to use the sameRNTI value.

Additionally, if the base station indicates NACK for UL data to the UE,it may be configured to indicate related adaptive retransmissioninformation to a corresponding DCI field or NPDSCH payload scheduled bythe corresponding DCI.

FIG. 22 illustrates the method described above.

FIG. 22 illustrates a method of multiplexing different PURs andACK/NACK.

As illustrated in FIG. 22, it can be seen that ten UEs with differentstarting subframes transmit UL data on four different UL carriers.Characteristically, there may be one or multiple PURs given to each UEin the corresponding PUR window, and the base station may be configuredto indicate ACK/NACK by reflecting the corresponding information. Inthis instance, the ACK/NACK is transmitted by being multiplexed to a DLconfigured carrier indicated in advance by the base station. Thisconfiguration has an advantage in terms of network overhead in thatACK/NACK of multiple UEs can be collected and transmitted at once.

Here, a feedback channel may also be determined as a specific window,and a UE needs to receive a feedback channel during a correspondingduration. This is because if resources used by UEs in the idle modeoverlap a resource for a connected mode UE, the resource of theconnected mode UE can be transmitted with a higher priority. Further, anactual duration of the corresponding window may vary depending on anoperation mode in NB-IoT and/or whether a NB-IoT DL carrier is an anchorcarrier or a non-anchor carrier. In case of MTC, it may vary dependingon a system bandwidth and/or a duplex mode and/or frequency hopping.

As another method for the base station to multiplex ACK/NACK, it may beconsidered a method that configures such that the UE transmits UL datato a PUR and monitors an UL grant in a predetermined number of subframesor during a predetermined time duration. That is, if subframes locationsfor CSS are equally configured and the monitoring is required at thesame place, the above-described method may be a method that configuressuch that the UE transmits UL data to a PUR and monitors an UL grant ina predetermined number of subframes or during a predetermined timeduration. This method is characterized in that different UEs monitor ULgrants at different locations, but the base station designates thecorresponding predetermined number of subframes or predetermined timeduration.

Further, when there is no more UL grant (e.g., retransmission UL grant)within the predetermined number of subframes or the predetermined timeduration, the UE may be configured to delete a buffer containing the ULdata that has been transmitted to the PUR. Alternatively, the basestation may be configured to indicate to the UE the content thatretransmission is no longer required using a specific field of the aboveUL grant or a combination of specific field values (e.g., NDItoggle+specific TBS value or specific RA value). If the base stationsupports the corresponding method, a battery saving effect of the UE canbe improved.

Additionally, it may be configured to naturally transmit an additionalTB and extend a time duration for viewing the search space whenreceiving the NDI toggled UL grant within the predetermined number ofsubframes or the predetermined time duration. Characteristically, thisoperation can be applied when an SR/BSR has been transmitted to aprevious PUR.

1-2 Embodiment: Retransmission Resource Selection Details

Next, there is proposed a detailed method that selects/configures aretransmission resource when initial transmission transmitted by a UEbecomes NACK so a base station requests retransmission.

Most simply, the base station may indicate to the UE that the UEperforms adaptive retransmission through a specific field of DCIindicating ACK/NACK. The UE receiving this indication may be configuredto perform retransmission of UL data to a location scheduled by thecorresponding DCI field. However, it may be preferable to apply thismethod when UE contention is ongoing in the shared resource type of PUR.In this case, depending on whether the UE monitors the feedback for theinitial transmission or monitors the feedback for the retransmissioneven though the UE transmits the same data, the search space may bedifferent or the DCI configuration may be different.

On the other hand, in the dedicated resource type of PUR, the basestation may be configured to indicate non-adaptive retransmission.Characteristically, the base station may also indicate non-adaptiveretransmission to a next PUR that exists immediately after receivingcorresponding ACK/NACK. This configuration has an advantage that thebase station does not need to allocate an additional UL resource for PURretransmission. However, there is also a disadvantage that the initialtransmission of other data intended to be sent to the next PUR may bedelayed due to retransmission of the previous data.

The base station may indicate the non-adaptive retransmission topre-configured additional UL resources via higher layer signaling. Inthis method, it may be configured that the PUR is a concept that is usedentirely for the initial transmission, and a UL resource dedicated forthe retransmission is additionally configured to the UE. This method hasan advantage that resources for the initial transmission are alwayssecured, and also has an advantage that it is not necessary to allocatean additional UL resource when much retransmission does not occur. Inthis case, depending on whether the UE monitors the feedback for theinitial transmission or the feedback for the retransmission even thoughthe UE transmits the same data, the search space may be different or theDCI configuration may be different.

Among the above-described methods, in methods which define feedback forPUR and consider that the base station transmits ACK/NACK to thecorresponding feedback channel, if, at this point, a UE does not receiveDCI indicating the ACK/NACK, the UE may be configured to operate asfollows.

Since it is explicitly configured to transmit ACK/NACK through DCI, ifthe UE does not receive the DCI indicating ACK/NACK, the UE may decidethat a problem has occurred in the corresponding PUR transmission (i.e.,NACK) and may perform retransmission to a resource for retransmission orto a PUR that exists thereafter. If resources for retransmission areconfigured as described above, there is an advantage in that reliabilityof data transmission of the UE is increased, but there may be adisadvantage from the battery life perspective of the UE because theretransmission shall be continuously performed until the DCI indicatingACK/NACK is received from the base station. On the other hand, in orderto address the disadvantage, if the UE fails to receive the DCIindicating ACK/NACK, the UE decides that there is no problem intransmission of the corresponding PUR (i.e., ACK) and does not performretransmission but performs initial transmission of other data to a PURthat exists thereafter. There may be an advantage from the battery lifeperspective of the UE, but there may be a disadvantage from the datareliability perspective. It may be configured to designate what tooperate among the two methods when the base station allocates a firstPUR to the UEs, or it may be configured to define one of the two methodsin the disclosure. If the base station designates when allocating thefirst PUR, the base station may be configured to indicate itUE-specifically or resource-specifically (or cell/CE level-specifically)according to a service type. This method may also be applied to themethod using the above group ACK/NACK.

In addition, if feedback for the PUR is defined and if a UE supposed toreceive ACK/NACK on a corresponding feedback channel does not receiveany feedback (e.g., ACK/NACK) a specific number of times (in this case,the specific number of times may be defined in base stationconfiguration or speciation), the corresponding UE may be configured torelease the corresponding PUR. In other words, the UE is supposed toreceive feedback, and if the UE has performed the PUR transmission butthere is no feedback therefor, the UE may determines that there is aproblem with the corresponding PUR transmission because the base stationmay not know that the corresponding UE is performing the transmission.Therefore, it may be configured that the PUR can be released.

As another method, it may be configured such that the base stationtransmits to the UE ACK/NACK and a retransmission grant through DCI.That is, it may be configured that a 1-bit field indicating ACK/NACKalways exists, and it may be configured that if the base stationindicates NACK through a corresponding field, the UE performsretransmission by interpreting subsequent DCI fields (e.g., MCS, RU,repetition number, scheduling delay, etc.), and if the base stationindicates ACK through the corresponding field, the subsequent DCI fieldsare reserved. However, in this case, there is a disadvantage that thereare many reserved fields in the DCI in which ACK is indicated.Therefore, if NACK is indicated, it may be considered a method in whichthe consecutive DCI fields are other than configuration such as a legacyUL grant. That is, a retransmission-dedicated resource is alreadyindicated along with a PUR configuration, and an MCS/TBS, repetitionnumber, etc. may be configured to have the same value as a value usedfor initial PUR transmission or to have a short field indicating onlydelta. In other words, it can be seen as a method of using compact DCIas a whole. In this case, it is possible to solve the problem that manyreserved fields remain if when ACK is indicated.

Additionally, PUR UEs receiving ACK/NACK or a retransmission grantthrough DCI in a NPDCCH search space for feedback may be configured tomatch the payload size of the DCI used for the corresponding feedback tothe legacy DCI format N0/N1, and if so, the UEs can receive a DL grantin the NPDCCH search space for corresponding feedback. This means thatif a UE transmits MSG3 or the like through a PUR, then an NPDSCH can besubsequently scheduled, and the UE can receive an RRC connection messagesuch as connection (re-)establishment through the corresponding NPDSCH.To this end, the base station may be configured to scramble the DCI forthe DL grant by using the same RNTI as an RNTI value configured toscramble the feedback DCI, and if the UE is also configured to expect touse the same RNTI value, the UE can receive the feedback DCI and the DLgrant without increasing the number of DCI BDs in one search space.

In this instance, when the UE that has transmitted the PUR receivesexplicit ACK through the DCI on the feedback channel of thecorresponding PUR as in the above method, if a DL grant rather thanneither explicit ACK nor retransmission UL grant is transmitted to thecorresponding DCI, the UE may be configured to determine that thepreviously transmitted PUR is implicitly ACK. That is, in order totransmit explicit ACK and transmit a DL grant, a field indicatingACK/NACK and fields capable of indicating a DL/UL grant shall be presenttogether in one DCI field, but there is a disadvantage in that it isincreased further than the legacy DCI size by 1 bit. Therefore, it maybe configured that if the UE receives the DL grant from the base stationas feedback for PUR transmission, the PUR is determined as implicitlyACK and an operation indicated by the corresponding DL grant (e.g.,(N)PDCCH order or (N)PDSCH reception) is performed.

As another method, if a DL grant (neither explicit ACK nor aretransmission UL grant) is transmitted to DCI of a feedback channel ofa PUR transmitted by a UE, and if the content indicated by thecorresponding DL grant represents scheduling information of subsequent(N)PDSCH, it may be determined that the PUR transmitted by the UE isimplicitly ACK. It may be configured that if the content indicated bythe corresponding DL grant has been a (N)PDCCH ordered RACH procedureindication, it is determined that the PUR transmitted by the UE isimplicitly NACK and the RACH procedure is performed (withoutretransmission for PUR).

Characteristically, it can be set that if a DL grant is transmitted to aPUR feedback channel and the corresponding DL grant indicates an(N)PDCCH order, the base station may be configured to indicate a(N)PRACH preamble for a legacy RACH procedure and may also be configuredto indicate (N)PRACH preamble for a legacy EDT procedure. For example,if the corresponding DL grant indicates the (N)PDCCH order and if acorresponding cell and the UE support EDT, the UE/base station may beconfigured to explicitly indicate to a DCI format for the (N)PDCCH order(e.g., DCI format N1, DCI format 6-1A, B), by using 1 bit of reservedfield, whether it is the (N)PRACH preamble for the RACH procedure or the(N)PRACH preamble for the EDT procedure. Since there are many reservedfields in the DCI for the (N)PDCCH order, the total DCI length does notincrease so there is no big problem even if explicitly indicated.

As another method, if EDT is possible for both the UE and the basestation and if both an EDT resource and an RACH resource exist in acarrier index and a CE level (i.e., repetition number) indicated by the(N)PDCCH order, the base station may configure that the UE selects andtransmits the EDT. In this method, since the UE performs a PUR in theidle mode and performs the (N)PDCCH order in response to a request fromthe base station, it may be preferable to operate with the EDT ratherthan a legacy RACH. As such, if the base station can indicate the EDT inthe (N)PDCCH order, the UE may be configured to transmit retransmissionof the previous PUR through the EDT. Further, the UE may receive fromthe base station reconfiguration of the PUR through the EDT.

Among the proposed methods, if explicit ACK/NACK of the base station istransmitted to the UE on a PUR feedback channel, the following methodmay be considered instead of a method for the base station to add anduse an independent field for indicating an actual explicit ACK/NACK. Itmay be configured that the base station use a field, that is notnecessary when indicating PUR retransmission in the existing UL grant,to transmit explicit ACK/NACK. Table 53 shows DCI format N0 indicatingan NB-IoT UL grant. That is, a field that is not necessary when used asa UL grant for PUR retransmission is flag for format N0/format N1differentiation (i.e., it is not necessary when a DL grant is notreceived and only a UL grant is received), and redundancy version (i.e.,it is not necessary when it is configured that the initial transmissionUL grant for PUR is not provided). Therefore, the base station mayconfigure that the UE reinterprets the corresponding field (e.g., Flagfor format N0/format N1 differentiation or redundancy version or newdata indicator, etc. and all types of fields that is not necessary whenused as UL grant for PUR retransmission) as a field indicating explicitACK/NACK. It may be configured that if it is configured that the DLgrant along with the UL grant is transmitted to the PUR feedbackchannel, the redundancy version field is reinterpreted as a fieldindicating explicit ACK/NACK (in this instance, NACK may mean a UL grantthat indicates retransmission).

TABLE 53 Number Field of Bits Description Flag for format 1 0-N0, 1-N1N0/format N1 differentiation Subcarrier indication 6 When SubcarrierSpacing = 15 Khz See 36.213 Table 16.5.1.1-1 When Subcarrier Spacing =3.75 Khz nsc = Isc Resource assignment 3 See 36.213 Table 16.5.1.1-2Scheduling delay 2 See 36.213 Table 16.5.1-1 Modulation and coding 4 See36.213 Table 16.5.1.2-1 scheme Redundancy version 1 Repetition number 3See 36.213 Table 16.5.1.1-3 New data indicator 1 DCI subframe 2repetition number Total Number of Bits 23

As another method, explicit ACK may be defined similarly to the methodapplied to eMTC. The following explicit ACK has been discussed in Rel.15 eMTC, and in 36.212 clause 5.3.3.1.10 and 5.3.3.1.11, it isintroduced as follows.

If the Resource block assignment in format 6-0A is set to all ones,format 6-0A is used for the indication of ACK feedback, and all theremaining bits except Flag format 6-0A/format 6-1A differentiation andDCI subframe repetition number are set to zero.

<Omitted>

If the Modulation and coding scheme in format 6-0B is 4 bits and set toall ones, format 6-0B is used for the indication of ACK feedback, andall the remaining bits except Flag for format 6-0B/format 6-1Bdifferentiation and DCI subframe repetition number are set to zero.

In order to apply a similar method, a state not used for a UL grant inDCI format NO is the same as the following Tables 54 and 55.

TABLE 54 Subcarrier indication field (I_(sc)) Set of Allocatedsubcarriers(n_(sc))  0-11 I_(sc) 12-15 3 (I_(sc)−12) + {0, 1, 2} 16-17 6(I_(sc)−16) + {0, 1, 2, 3, 4, 5} 18 {0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10}19-63 Reserved

TABLE 55 I

I

0 1 2 3 4 5 6 7  0 16 32 56 88 120 152 208 256  1 24 56 88 144 176 208256 344  2 32 72 144 176 208 256 328 424  3 40 104 176 208 256 328 440568  4 56 120 208 256 328 408 552 680  5 72 144 224 328 424 504 680 872 6 88 176 256 392 504 600 808 1000  7 104 224 328 472 584 712 1000 1224 8 120 256 392 536 680 808 1096 1384  9 136 296 456 616 776 936 12561544 10 144 328 504 680 872 1000 1384 1736 11 176 376 584 776 1000 11921608 2024 12 208 440 680 1000 1128 1352 1800 2280 13 224 488 744 10321256 1544 2024 2536

indicates data missing or illegible when filed

Therefore, as a method of indicating a UL grant using an unused state ofDCI format N0, there may be a method for a UE/base station to configuresubcarrier indication fields to all ones and set the remaining bits(except for the Flag for format N0/format N1 differentiation field whenit is configured that a DL grant is transmitted along with a UL grant onthe PUR feedback channel) to zero. As another method, there may be amethod for a UE/base station to configure modulation and coding schemefields to all ones and set the remaining bits (except for the Flag forformat N0/format N1 differentiation field when it is configured that theDL grant is transmitted along with the UL grant on the PUR feedbackchannel) to zero. In this instance, since the modulation and codingscheme field has only 2 states (i.e., 14, 15) as reserved states and canbe used for enhancement later, it may be more preferable to use thesubcarrier indication field, which has a relatively large margin ofreserved states (i.e., 48-63) and which is not easy to enhance later.

Additionally, the following method may be considered as a method for aUE/base station to indicate explicit NACK through a UL grant. Similar tothe above proposal, a method for a UE/base station to configure aspecific field (e.g., the subcarrier indication field) with a reservedstate to all one and set the remaining bits to zero may be configured asexplicit NACK. However, when explicit ACK is indicated by a method ofconfiguring a specific field (e.g., subcarrier indication field) withthe reserved state to all one and setting the remaining bits to zero, amethod for a UE/base station to set the least bit value of the specificfield (e.g., subcarrier indication field) with the reserved state (e.g.,subcarrier) to 0 for explicit NACK and set the remaining bits to 1(e.g., 111110) may be employed, and the remaining fields may be set tozero. That is, if this example is described in a different expression,it is a method for a UE/base station to use 63 of the reserved states ofthe subcarrier indication field as explicit ACK and use 62 of thereserved states as explicit NACK while all other bits are zero. Usingthis method has an advantage that an additional 1-bit field for ACK/NACKis not required. However, if explicit NACK is configured to use areserved state as proposed above, there is a disadvantage in that thebase station cannot indicate, to a UE, a UL resource for retransmission.If this method is used, the UE may be configured to receive explicitNACK and to select and perform either the RACH/EDT procedure ortransmission to the next PUR.

In addition, as a method for the base station to more clearly indicatean operation of the UE, it may be configured to use a plurality ofreserved states of a specific field (e.g., subcarrier indication field)with reserved states for explicit NACK. That is, for example, the basestation may configure that 63 of the reserved states of the subcarrierindication field indicates explicit ACK while all other bits are zero,configure that 62 of the reserved states of the subcarrier indicationfield indicates explicit NACK, indicate that the UE performs the (CB)RACH procedure, configure that the reserved state 61 of the subcarrierindication field indicates an explicit NACK, indicate that the UEperforms the (CB) EDT procedure, configure that reserved state 60 of thesubcarrier indication field indicates explicit NACK, and indicate thatthe UE performs retransmission to the next PUR occasion (or a PURoccasion pre-configured by the base station). This method may be said tobe a desirable operation in that the base station can accuratelyindicate a subsequent operation of the UE.

The proposed method of indicating explicit NACK through a UL grant canalso be applied to eMTC. That is, in the case of CE mode A using format6-0A, it may be configured to indicate explicit NACK by additionallyusing a reserved state of a resource block assignment field, and in thecase of CE mode B using format 6-0B, it may be configured to indicateexplicit NACK by additionally using a reserved state of the modulationand coding scheme.

In the above proposal, the reason why a specific state of the UL grant(where, the UL grant means a case where a downlink feedback channel(e.g., DCI) for PUR transmission is interpreted as a purpose forindicating uplink scheduling) is used to notify “data that the UEtransmits to the PUR has failed to be detected by the base station” maybe to indicate a fallback (e.g., entering a data transmission procedurethrough an EDT or a random access process) through a legacy operation,not to allocate a new resource for retransmission through thecorresponding UL. That is, when it is determined that new resources tobe allocated for retransmission by the UE are insufficient or that thereason for the failure to detect data previously received from the PURis a transmission timing of the UE or that it is determined that thereis a problem with the transmit power, the base station may fallback to alegacy operation so that transmission timing and power can be readjustedrather than allocating new uplink resources. Such an operation may beindicated by fixing the resource of the UL grant to a specific state(not indicating an actual uplink transmission resource) while indicatingexplicit NACK in a downlink feedback channel, and explicit NACK may beimplicitly indicated by indicating a specific state other than a statewhich exists as a field independent of the UL grant or is used toindicate an actual uplink transmission resource within the UL grant, andcombinations of the above-described specific fields may be examplestherefor. In addition, a state not used in the UL grant may be used toindicate the release.

Additionally, when ACK/NACK for PUR is transmitted on (N)PDSCH(s), ifthe UE decodes DCI(s) for scheduling a corresponding (N)PDSCH(s) butfails to decode the corresponding (N)PDSCH(s), the base station mayconfigure that the UE may regard the corresponding PUR as NACK, and thefeedback (ACK/NACK) for the corresponding (N)PDSCH(s) does not need tobe sent. That is, if the UE does not receive it although ACK/NACK istransmitted to DCI, the UE may regard the PUR as NACK, and even if theUE receives DCI but fails to decode the (N)PDSCH(s), the UE may regard acorresponding PUR as NACK. In this instance, since it is not necessaryto use the HARQ-ACK resource field (4bits) of DCI format N1 if it isconfigured that a feedback for the (N)PDSCH(s) is not required, it maybe configured to reverse the corresponding field or to reduce a DCI sizewithout using the field. In this instance, it is preferable to match aDCI payload size to perform BD on the DL grant and the UL grant as oneRNTI. In addition, even if the UE succeeds to decode the corresponding(N)PDSCH(s), when the corresponding (N)PDSCH(s) is used to indicateACK/NACK for PUR transmission, the ACK/NACK therefor may not be reportedto an uplink. In such a case, a field used to indicate an ACK/NACKresource in DCI that schedules the corresponding (N)PDSCH(s) may be usedfor a different purpose or may be set to a random value or may notexist. Exceptionally, when the UE indicates the PUR release on the(N)PDSCH(s), the UE may report ACK (or NACK) therefor or transmit aresponse thereto on the (N)PUSCH. However, in the case of using the(N)PUSCH, information for configuring a UL resource such as a UL grantmay be included in the (N)PDSCH. As described above, if an operation tobe performed by the UE after interpretation of the (N)PDSCH informationand/or detection of the corresponding (N)PDSCH may vary, the DCI thatschedules the corresponding (N)PDSCH may include a method forinterpretation information of the corresponding (N)PDSCH and indicationinformation related to a subsequent operation of the UE.

In addition, if the payload size of DCI used for the feedback purpose isnot matched to the legacy DCI format N0/N1 and a shorter compact DCI isused, a slightly different method may be applied. That is, if the UEtransmits something such as MSG3 through a PUR, it may be configured toreceive a DL grant in a legacy common search space (e.g., Type 1/2,1A/2A NPDCCH CSS) that exists after a transmission time point. In thisinstance, the UE may configure that which legacy common search space theUE should monitor, and this is summarized as follows. Even in this case,a RNTI value that scrambles DCI for the corresponding DL grant may beconfigured to use the same value as the RNTI value that scrambles thefeedback DCI of the PUR.

1) In the simplest way, it may be configured that the base stationindicates to the UE which legacy common search space the base stationshall monitor to receive the DL grant along with PUR configuration. Inthe case of a contention-free PUR, it may be configured to be designatedUE-specifically, and in the case of contention-based PUR, it may beconfigured to be designated cell/resource (e.g., PUR)-specifically.Characteristically, it may be configured that a carrier index, a CElevel, a period, Rmax, etc. are included as legacy common search spaceinformation.

2) In another method, a legacy common search space associated with a PURresource may be implicitly designated. For example, it may be configuredto monitor a legacy common search space that exists after X subframepassed from an end time of the PUR transmission among the legacy commonsearch spaces that exist in the DL carrier corresponding to a UL carriertransmitting the PUR resource, and if the common search space does notexist in the corresponding carrier, it may be configured to monitor alegacy common search space that exists after X subframe passed from atime when PUR transmission ends in an anchor carrier. The aforementionedlegacy common search spaces may be Type 1/2, 1A/2A NPDCCH CSS, etc.

3) In a third method, a special search space is defined separately froman NPDCCH search space used for the feedback purpose, and thus it may beconfigured to receive the DL grant through a special search space thatis indicated separately if the UE transmits MSG3, etc. to the PUR.Characteristically, a period of the special search space may be definedto be N times a period of the PUR resource, and the UE may be configuredto transmit MSG3, etc. to the PUR immediately before a timing in whichthe corresponding special search space exists, where N may be a valueless than 1. This may be the purpose of receiving indication ofACK/NACK, etc. when data, to which the retransmission is indicated, isretransmitted in a new uplink resource after the PUR that hastransmitted the corresponding data, not after the next PUR. That is,when N is less than 1, if ACK for the PUR transmission is indicated, aspecial search space between a time of reception of the ACK and a nextPUR may be allowed so that the UE cannot perform the monitoring. Inaddition, an NRS that the UE can always expect may be limited to aspecific duration regardless of whether downlink feedback information isactually transmitted in the corresponding special search space.

Characteristically, when it is configured that the base station canexplicitly configure a downlink carrier index in which a feedbackchannel is transmitted along with PUR configuration and when thedownlink carrier index is actually explicitly configured, the UE mayreceive the feedback channel in the configured downlink carrier. If thebase station does not specifically configure the downlink carrier inwhich the corresponding feedback channel (e.g., search space, etc.) canbe transmitted, it may be configured to be basically delivered to ananchor carrier or it may be configured that the feedback channel isdelivered to a DL carrier corresponding to a UL carrier in which PUR isconfigured.

In addition, when the base station indicates the UL grant to thefeedback channel of the PUR, the UE may be configured to always regardit as indicating retransmission for the previously transmitted PUR andto perform retransmission for the same TB.

In addition, considering that the feedback channel of PUR is designedsimilarly to a legacy NPDCCH search space, a starting SF of the legacysearch space is determined by an equation using Rmax, npdcch-StartSF,and npdcch-Offset that the base station indicates as higher layerparameters. However, it may be undesirable that the search space inwhich the PUR feedback channel is transmitted is not related to PURtransmission, and it may be desirable to have a search space for thecorresponding feedback channel after the PUR transmission proceeds.Therefore, in a (NB-IoT) DL subframe after X ms or X (NB-IoT) DLsubframe (e.g., X=4) passed from a PUR transmission start UL subframe ora PUR transmission end UL subframe, the (NB-IoT) DL subframe obtained byadding a value calculated using Rmax, npdcch-StartSF, and npdcch-Offsetof the corresponding search space that the base station indicates ashigher layer parameters may become the starting subframe of thecorresponding search space. Characteristically, a corresponding DL/ULsubframe may be configured based on a valid subframe. In addition, ifthe UE receives HARQ feedback in the form of DCI from the base station,the base station may indicate a specific multiple of the period (i.e.,NPDCCH Period) of the corresponding search space as a feedback window ormay be defined and configured in the present disclosure. That is, if thebase station has set N number of times of the search space period inwhich feedback DCI can be transmitted as the feedback window, the UE maytransmit PUR and shall monitor whether feedback DCI is transmitted for atime corresponding to N times the search space period. If the feedbackDCI has been received in a search space (or search space candidate) of aspecific location while the UE is monitoring as much as thecorresponding feedback window, it may be configured that other searchspaces (or other search space candidates) in the next feedback window donot need to be monitored. In this configuration, there is an advantagein terms of the battery life of the UE because the UE does not need toperform additional monitoring.

In a search space that a UE monitors after transmitting data to the PUR(the corresponding search space may be a channel for schedulingretransmission or HARQ feedback for data transmitted to the PUR or maybe configured to the UE for (a-)periodically transmitted channel for TAand/or TPC adjustment), it may be configured that the UE can expect areference signal (e.g., NRS) regardless of whether or not the feedbackchannel is transmitted in the corresponding search space. This may bethe purpose of an automatic gain control (AGC) of the UE, time/frequencysync., early blind detection termination, etc. Here, a subframe in whichthe NRS can be transmitted may be limited to Y subframe after the startof the search space from a location preceding a subframe configured suchthat the search space is transmitted (e.g., a subframe preceding the Xsubframe, where X is a positive integer), where Y may vary depending ona length of the corresponding search space (e.g., maximum length/numberof repeated transmissions).

For the above purposes (e.g., the UE's AGC, time/frequency sync., etc.)and for UL power control through TA validation and DL path lossmeasurement, a subframe in which the UE can always expect an NRS may beadditionally configured at a time point that is earlier than the PUR byZ subframe (where Z is a positive integer). That is, a downlink subframefor this purpose may be configured in a positional relationship relativeto the PUR, and a transmission period may also be indirectly derivedfrom a parameter related to a PUR period. However, the correspondingdownlink subframe may not exist for each PUR, and for example, asubframe for this purpose (which means that the UE can expect an NRS)may be configured before the Z subframe every K PURs (i.e., every K-thPUR).

The downlink carrier, in which the search space monitored by the UEafter transmission of data to a PUR considered in the method proposedabove can be transmitted, includes not only an anchor carrier but also anon-anchor carrier.

Additionally, when retransmission is performed on a PUR, a method fordistinguishing whether UL data transmitted to the corresponding PUR isinitial transmission or retransmission may be required for the basestation. Characteristically, in a contention-free PUR (e.g., dedicatedPUR, contention free shared PUR), the base station may UE-specificallyindicate a DMRS sequence for the initial transmission and a DMRSsequence for the retransmission. Alternatively, for the DMRS sequencefor the retransmission, a sequence having a specific relationship fromthe DMRS sequence may be indicated by the base station or may be definedin the present disclosure. In this instance, the specific relationshipmeans that an index for the initial transmission among indexes forselecting a base sequence of DMRS sequences may be indicated by the basestation (e.g., k), that an index for the retransmission may be definedas (k+m) mod N (where N is the total number of base sequences for eachlength, and mod is a modular operation), and that a value of m may bedefined UE-specifically or cell-specifically. For the contention-basedshared PUR, the base station may configure cell/CE mode-specifically orresource (e.g., PUR)-specifically the DMRS sequence set for the initialtransmission and the DMRS sequence set for the retransmission.Alternatively, the above-proposed relationship between the DMRS sequencefor the initial transmission and the DMRS sequence for theretransmission is also applied here, and when the UE selects the DMRSsequence for the initial transmission, the DMRS sequence for theretransmission may be configured to be determined according to thecorresponding rule. In this configuration, there is an advantage thatthe base station can determine, through DMRS detection, whether the ULdata to be transmitted to a specific PUR is initially transmitted orretransmitted. Characteristically, the DMRS sequence may be applied bysubstituting a specific sequence known to each other between the basestation and the terminal.

Next, even though the base station sets an RNTI value that the PUR UEcan use, if the number of idle mode UEs to perform PUR increases,overlapping with a C-RNTI value for a connected mode UE may beinevitable. In addition, the base station may configure search spacessmartly and independently not to cause a collision, but since there isno guarantee for the UE that the base station always configures thesearch spaces smartly, there may be some cases where a search spacededicated to PUR feedback and a UE-specific search space of anotherconnected mode UE partially overlap. Therefore, in order to solve thisproblem, the following method may be considered.

Method 1:

If a DCI payload size for delivering PUR feedback is made the same as apayload size of any one of legacy DCI formats NO/N1/N2, the DCI payloadsize may be configured to be different all the time by adding anarbitrary bit(s) (e.g., 1 bit zero padding) to DCI that delivers a PURfeedback. If this is applied to eMTC, it may be configured by applyingit to legacy DCI formats 6-0A/6-1A/6-0B/6-1B/6-2. As such, if the DCIpayload size is always different, there is an advantage that ambiguitydoes not occur between UEs even if a plurality of RNTI values isoverlapped.

Method 2:

As another method, the number of bits of RNTI used to scrambling DCI fordelivering PUR feedback may be set to be more than the number of bits ofRNTI used in the connected mode, and it may be configured that one ofRNTI values not overlapping with the RNTI values used in the connectedstate is assigned to a PUR UE. For example, when the number of RNTI bitsis increased by n bits, one of values from 216 to 216+n−1 may beselected and allocated, except for values from 0 to 216-1 which legacy16 bits RNTI can have.

Method 3:

In another method, a method may be considered, which allowsinitialization of a scrambling sequence used for DCI for delivering PURfeedback to be different from initialization of a legacy NPDCCHscrambling sequence. As such, if the initialization of the scramblingsequence is configured differently as described above, there is anadvantage that ambiguity does not occur in decoding DCI between UEs withoverlapping RNIT values.

Method 4: In another method, a method may be considered, which removesambiguity between UEs, differently from a legacy DCI mapping method, ina DCI RE mapping step for the purpose of delivering PUR feedback.Currently, the legacy DCI mapping is being performed as follows.

“The mapping to resource elements (k, l) on antenna port p meeting thecriteria above shall be in increasing order of first the index k andthen the index l, starting with the first slot and ending with thesecond slot in a subframe”. Therefore, “decreasing order of first indexk and then the index l, starting with the first slot and ending with thesecond slot in a subframe” may be configured to be applied by settingthe mapping order to the decreasing order not the increasing order inthe DCI RE mapping step for the purpose of delivering feedback of PUR,“increasing order of first the index l and then the index k, startingwith the first slot and ending with the second slot in a subframe” maybe configured to be applied by reordering the index k and the index l,and “increasing order of first the index k and then the index l,starting with the second slot and ending with the first slot in asubframe.” may be configured to be applied by applying the mappingmethod starting with the second slot and ending with the first slot.

Second Embodiment: Transmit Power Control for Preconfigured UL Resource(PUR)

A transmit power control method for PUR is described in detail below.

2-1 Embodiment: PUR Transmit Power Ramping Depending on Number ofTransmissions and/or Number of Feedback Receptions

First, a method of TX power ramping for PUR depending on the number oftransmissions and/or the number of feedback receptions may beconsidered. Characteristically, the power ramping method may be mainlyapplied to PUR of a shared resource type that requires contentionbetween UEs.

The base station may be configured to indicate initial TX power that canbe used when transmitting UL data in the PUR. Alternatively, it may beconfigured that the corresponding TX power value is determined in thepresent disclosure. Thereafter, the UE may be configured to transmit ULdata to the PUR using the corresponding initial TX power value. In thisinstance, the base station may be configured to give feedback for thecorresponding UL data, and the base station may be configured toindicate, to the UE, a location at which the corresponding feedback isgiven. Here, the initial TX power may be different from TPC fortransmission of an existing (N)PRACH preamble, and one or more TPCsettings may exist according to resources that the UE can select fromshared resources (e.g., (N)PUSCH resource or TBS, etc.).

After the UE transmits UL data to a PUR using an initial TX power value,if the feedback has not been received although there was an opportunitythat a feedback could be transmitted from the base station as many timesas a specific number of times (e.g., N number of times, where N is apositive integer greater than or equal to 1) which is preset or isindicated by the base station, it may be configured to ramp the TX powerin the next PUR transmission. Characteristically, a power rampinginterval may also be configured as indicated by the base station, andthe number of times that the power can be ramped at maximum may also beconfigured as indicated by the base station. If the UE receives NACK isreceived after transmitting UL data to a PUR, the UE transmits the ULdata while maintaining the existing TX power as many times as a specificnumber of times (e.g., M number of times, where M is a positive integergreater than or equal to 1) which is preset or is indicated by the basestation. If NACK is continuously received even after the UL data hasbeen transmitted M number of times, it may be configured to performpower ramping when next UL data is transmitted.

Thereafter, if the UE transmits UL data using MAX power that can betransmitted through the power ramping by repeating the aforementionedpower ramping, the UE may be configured to change a resource type or tochange a period of a PUR if the feedback has not been received althoughthere was an opportunity that a feedback could be transmitted by thebase station as many times as a specific number of times (e.g., L numberof times, where L is a positive integer greater than or equal to 1)which is preset or is indicated by the base station. Alternatively, itmay be configured that the UE requests the base station to change theresource type. Characteristically, in order to configure this way, thebase station shall configure a plurality of PURs in a correspondingcell, and the resource type need to be configured with both thededicated resource type and the shared resource type. If the UEtransmits a request to change the resource type from the shared resourceto the dedicated resource and the base station wishes to respond to therequest, the base station may newly configure a UE-specific PUR to thecorresponding UE. In this instance, the base station may be configuredto change the resource type as requested by the UE and also newlyindicate TX power. Alternatively, if the UE receives an indication ofthe base station that the resource type can be changed, it may beconfigured to be reset to the initial TX power value used for a previousPUR.

On the other hand, after the UE transmits UL data to a PUR using aspecific TX power value, if the UE has received ACK within a presetspecific time as many times as a specific number of times (e.g., Cnumber of times, where C is a positive integer greater than or equalto 1) which is preset or is indicated by the base station, the UE may beconfigured to reduce the TX power in the next PUR transmission.Characteristically, an interval for reducing power may be set asindicated by the base station, and the smallest TX power value may alsobe set as indicated by the base station.

In addition, if the UE fails to transmit PUR more than a preset specificnumber of times (e.g., N number of times) using MAX power that can betransmitted through the power ramping by repeating the aforementionedpower ramping, it may be configured to self-release the correspondingPUR and perform a fallback operation. Here, the fallback operation mayinclude attempting to transmit data through an EDT procedure, performinga RACH procedure for entering an RRC connected mode, or performing apredefined operation for TA update. If a PUR is shared with other users,after a transmission failure in the PUR at a specific location, datatransmission is not immediately performed at a subsequent PUR and it maybe configured that data transmission is performed in a PUR at a presetlocation.

Thereafter, if the UE transmits UL data using MAX power that can betransmitted through the power ramping by repeating the aforementionedpower ramping, the UE may be configured to change a resource type or tochange a period of a PUR if the feedback has not been received althoughthere was an opportunity that a feedback could be transmitted by thebase station as many times as a specific number of times (e.g., L numberof times, where L is a positive integer greater than or equal to 1)which is preset or is indicated by the base station. Alternatively, itmay be configured that the UE requests the base station to change theresource type. Characteristically, in order to configure this way, thebase station shall configure a plurality of PURs in a correspondingcell, and the resource type need to be configured with both thededicated resource type and the shared resource type. If the UEtransmits a request to change the resource type from the shared resourceto the dedicated resource and the base station wishes to respond to therequest, the base station may newly configure a UE-specific PUR to thecorresponding UE. In this instance, the base station may be configuredto change the resource type as requested by the UE and also newlyindicate TX power. Alternatively, if the UE receives an indication ofthe base station that the resource type can be changed, it may beconfigured to be reset to the initial TX power value used for a previousPUR.

On the other hand, after the UE transmits UL data to a PUR using aspecific TX power value, if the UE has received ACK within a presetspecific time as many times as a specific number of times (e.g., Cnumber of times, where C is a positive integer greater than or equalto 1) which is preset or is indicated by the base station, the UE may beconfigured to reduce the TX power in the next PUR transmission.Characteristically, an interval for reducing power may be set asindicated by the base station, and the smallest TX power value may alsobe set as indicated by the base station.

In addition, if the UE fails to transmit PUR more than a preset specificnumber of times (e.g., N number of times) using MAX power that can betransmitted through the power ramping by repeating the aforementionedpower ramping, it may be configured to self-release the correspondingPUR and perform a fallback operation. Here, the fallback operation mayinclude attempting to transmit data through an EDT procedure, performinga RACH procedure for entering an RRC connected mode, or performing apredefined operation for TA update. If a PUR is shared with other users,after a transmission failure in the PUR at a specific location, datatransmission is not immediately performed at a subsequent PUR and it maybe configured that data transmission is performed in a PUR at a presetlocation.

2-3 Embodiment: Transmit Power Configuration for PUR Transmission

Next, a method of configuring UL TX power of a UE for PUR transmissionis proposed. In the simplest method, it may be configured that a UE thatenters an idle mode and wishes to transmit a PUR uses as it is TX powerused for (N)PUSCH transmission used in the connected mode immediatelybefore entering the idle mode. Here, using as it is the TX power usedfor the (N)PUSCH transmission may mean using as it is a component amongTX power components, except for a value that varies depending on a pathloss measurement value, the number of RB/subcarriers used for the(N)PUSCH transmission, and a coding rate. Alternatively, it may beconfigured to use a value obtained by adding a specific offset to allthe corresponding TX power values (or a specific parameter forcalculating the TX power values), and it may be configured that thespecific offset is indicated by the base station UE-specifically,PUR-specifically, CE level-specifically, or the like.

Characteristically, if PUR configuration is not proceeded in theconnected mode (e.g., if the PUR configuration is indicated throughEDT), it may be configured to use as it is TX power values used forPUSCH transmission containing MSG3, and it may be configured to use avalue obtained by adding a specific offset to all the corresponding TXpower values (or to a specific parameter for calculating the TX powervalues). Characteristically, in NB-IoT, it may be configured todetermine the TX power such as (NPRACH target power)/(MSG3 targetpower)+specific offset (e.g., delat_preamble_MSG3). In eMTC, it may beconfigured to determine the TX power such as (PRACH targetpower)+specific offset (e.g., delat_preamble_MSG3). It may be configuredthat the aforementioned specific offset is indicated by the base stationUE-specifically, PUR-specifically, CE level-specifically, or the like.

The proposed methods may be applied when it not in CE mode B in the caseof eMTC, and in the case of NB-IoT when the number of RU repetitions is2 or less and when the enhanced random access power control is notconfigured while the number of RU repetitions is 2 or more. That is, theabove proposed method may be applied when it is in CE mode B in the caseof eMTC, and in the case of NB-IoT when the enhanced random access powercontrol is configured while the number of RU repetitions is 2 or more,but it may be configured to transmit using the maximum TX power of a PURtransmission UE.

FIG. 23 is a flow chart illustrating a method for a UE to controltransmit power in a wireless communication system supporting narrowband(NB)-Internet of Things (IoT) according to an embodiment of the presentdisclosure.

First, a UE may receive, from a base station, a preconfigured uplink(UL) resource (PUR) configuration via RRC signalling in S2301.

Subsequently, the UE may transmit, to the base station, uplink data onthe PUR in S2303.

Finally, the UE may receive, from the base station, feedback informationfor the uplink data in S2305.

A ramping interval of the transmit power is indicted from the basestation.

The UE may transmit the uplink data in an idle mode, and the transmitpower may be a transmit power used in a connected mode with the basestation before entering the idle mode.

A specific offset value may be added to a current transmit power.

The transmit power of the uplink data may be controlled based on thenumber of transmissions of the uplink data.

The UE may control the transmit power of the uplink data based on thenumber of receptions of feedback information.

FIG. 24 is a flow chart illustrating a method for a base station totransmit a feedback to a UE in a wireless communication systemsupporting NB-IoT according to an embodiment of the present disclosure.

First, a base station may transmit, to a UE, a preconfigured uplink (UL)resource (PUR) configuration via RRC signalling in S2401.

Subsequently, the base station may receive, from the UE, uplink data onthe PUR in S2403.

Finally, the base station may transmit, to the UE, feedback informationfor the uplink data in S2405.

The feedback may be configured to be transmitted on NPDCCH after aspecific time after receiving the PUR.

A UE or a device described in the present disclosure with reference toFIGS. 25 to 29 may be implemented to perform methods described in thepresent disclosure with reference to FIGS. 23 and 24.

Example of Communication System to which the Present Disclosure isApplied

Although not limited thereto, but various descriptions, functions,procedures, proposals, methods, and/or operation flowcharts described inthe present disclosure can be applied to various fields requiringwireless communication/connection (e.g., 5G) between devices.

Hereinafter, the communication system will be described in more detailwith reference to drawings. In the following drawings/descriptions, thesame reference numerals will refer to the same or corresponding hardwareblocks, software blocks, or functional blocks, if not differentlydescribed.

FIG. 25 illustrates a communication system 1 applied to the presentdisclosure.

Referring to 25, a communication system 1 applied to the presentdisclosure includes a wireless device, a BS, and a network. Here, thewireless device may mean a device that performs communication by using awireless access technology (e.g., 5G New RAT (NR) or Long Term Evolution(LTE)) and may be referred to as a communication/wireless/5G device.Although not limited thereto, the wireless device may include a robot100 a, vehicles 100 b-1 and 100 b-2, an eXtended Reality (XR) device 100c, a hand-held device 100 d, a home appliance 100 e, an Internet ofThing (IoT) device 100 f, and an AI device/server 400. For example, thevehicle may include a vehicle with a wireless communication function, anautonomous vehicle, a vehicle capable of performing inter-vehiclecommunication, and the like. Further, the vehicle may include anunmanned aerial vehicle (UAV) (e.g., drone). The XR device may includean augmented reality (AR)/virtual reality (VR)/mixed reality (MR) deviceand may be implemented as a head-mounted device (HMD), a head-up display(HUD) provided in the vehicle, a television, a smart phone, a computer,a wearable device, a home appliance device, digital signage, a vehicle,a robot, etc. The hand-held device may include a smart phone, a smartpad, a wearable device (e.g., a smart watch, a smart glass), a computer(e.g., a notebook, etc.), and the like. The home appliance device mayinclude a TV, a refrigerator, a washing machine, and the like. The IoTdevice may include a sensor, a smart meter, and the like. For example,the base station and the network may be implemented even as the wirelessdevice, and a specific wireless device 200 a may operate as a basestation/network node for other wireless devices.

The wireless devices 100 a to 100 f may be connected to a network 300over a base station 200. An artificial intelligence (AI) technology maybe applied to the wireless devices 100 a to 100 f, and the wirelessdevices 100 a to 100 f may be connected to an AI server 400 over thenetwork 300. The network 300 may be comprised using a 3G network, a 4G(e.g., LTE) network, or a 5G (e.g., NR) network. The wireless devices100 a to 100 f may communicate with each other over the base station200/network 300, but may directly communicate with each other withoutgoing through the base station/network (sidelink communication). Forexample, the vehicles 100 b-1 and 100 b-2 may perform directcommunication (e.g., Vehicle to Vehicle (V2V)/Vehicle to everything(V2X) communication). Further, the IoT device (e.g., sensor) may performdirect communication with other IoT devices (e.g., sensor) or otherwireless devices 100 a to 100 f.

Wireless communications/connections 150 a, 150 b, and 150 c may be madebetween the wireless devices 100 a to 100 f and the base station 200 andbetween the base station 200 and the base station 200. The wirelesscommunication/connection may be made through various wireless accesstechnologies (e.g., 5G NR) such as uplink/downlink communication 150 a,sidelink communication 150 b (or D2D communication), and inter-basestation communication 150 c (e.g., relay, integrated access backhaul(IAB)). The wireless device and the base station/the wireless device andthe base station and the base station may transmit/receive radio signalsto/from each other through wireless communications/connections 150 a,150 b, and 150 c. For example, the wireless communications/connections150 a, 150 b, and 150 c may transmit/receive signals on various physicalchannels. To this end, based on various descriptions of the presentdisclosure, at least some of various configuration information settingprocesses, various signal processing processes (e.g., channelencoding/decoding, modulation/demodulation, resource mapping/de-mapping,etc.), a resource allocation process, etc. for transmission/reception ofthe radio signal may be performed.

Example of Wireless Device to which the Present Disclosure is Applied

FIG. 26 illustrates a wireless device which may be applied to thepresent disclosure.

Referring to FIG. 26, a first wireless device 100 and a second wirelessdevice 200 may transmit/receive radio signals through various wirelessaccess technologies (e.g., LTE and NR). The first wireless device 100and the second wireless device 200 may correspond to a wireless device100 x and a base station 200 and/or a wireless device 100 x and awireless device 100 x of FIG. 25.

The first wireless device 100 may include one or more processors 102 andone or more memories 104 and may further include one or moretransceivers 106 and/or one or more antennas 108. The processor 102 maycontrol the memory 104 and/or the transceiver 106 and may be configuredto implement descriptions, functions, procedures, proposals, methods,and/or operation flows described in the present disclosure. For example,the processor 102 may process information in the memory 104 and generatefirst information/signal and then transmit a radio signal including thefirst information/signal through the transceiver 106. Further, theprocessor 102 may receive a radio signal including secondinformation/signal through the transceiver 106 and then store in thememory 104 information obtained from signal processing of the secondinformation/signal. The memory 104 may be connected to the processor 102and store various information related to an operation of the processor102. For example, the memory 104 may store a software code includinginstructions for performing some or all of processes controlled by theprocessor 102 or performing the descriptions, functions, procedures,proposals, methods, and/or operation flowcharts described in the presentdisclosure. The processor 102 and the memory 104 may be a part of acommunication modem/circuit/chip designed to implement the wirelesscommunication technology (e.g., LTE and NR). The transceiver 106 may beconnected to the processor 102 and may transmit and/or receive the radiosignals through one or more antennas 108. The transceiver 106 mayinclude a transmitter and/or a receiver. The transceiver 106 may bemixed with a radio frequency (RF) unit. In the present disclosure, thewireless device may mean the communication modem/circuit/chip.

The second wireless device 200 may include one or more processors 202and one or more memories 204 and may further include one or moretransceivers 206 and/or one or more antennas 208. The processor 202 maycontrol the memory 204 and/or the transceiver 206 and may be configuredto implement descriptions, functions, procedures, proposals, methods,and/or operation flows described in the present disclosure. For example,the processor 202 may process information in the memory 204 and generatethird information/signal and then transmit a radio signal including thethird information/signal through the transceiver 206. Further, theprocessor 202 may receive a radio signal including fourthinformation/signal through the transceiver 206 and then store in thememory 204 information obtained from signal processing of the fourthinformation/signal. The memory 204 may be connected to the processor 202and store various information related to an operation of the processor202. For example, the memory 204 may store a software code includinginstructions for performing some or all of processes controlled by theprocessor 202 or performing the descriptions, functions, procedures,proposals, methods, and/or operation flowcharts described in the presentdisclosure. The processor 202 and the memory 204 may be a part of acommunication modem/circuit/chip designated to implement the wirelesscommunication technology (e.g., LTE and NR). The transceiver 206 may beconnected to the processor 202 and may transmit and/or receive the radiosignals through one or more antennas 208. The transceiver 206 mayinclude a transmitter and/or a receiver, and the transceiver 206 may bemixed with the RF unit. In the present disclosure, the wireless devicemay mean the communication modem/circuit/chip.

Hereinafter, hardware elements of the wireless devices 100 and 200 willbe described in more detail. Although not limited thereto, one or moreprotocol layers may be implemented by one or more processors 102 and202. For example, one or more processors 102 and 202 may implement oneor more layers (e.g., functional layers such as PHY, MAC, RLC, PDCP,RRC, and SDAP). One or more processors 102 and 202 may generate one ormore protocol data units (PDUs) and/or one or more service data units(SDUs) according to the descriptions, functions, procedures, proposals,methods, and/or operation flowcharts described in the presentdisclosure. One or more processors 102 and 202 may generate a message,control information, data, or information according to the descriptions,functions, procedures, proposals, methods, and/or operation flowchartsdescribed in the present disclosure. One or more processors 102 and 202may generate a signal (e.g., a baseband signal) including the PDU, theSDU, the message, the control information, the data, or the informationaccording to the function, the procedure, the proposal, and/or themethod described in the present disclosure and provide the generatedsignal to one or more transceivers 106 and 206. One or more processors102 and 202 may receive the signal (e.g. baseband signal) from one ormore transceivers 106 and 206 and acquire the PDU, the SDU, the message,the control information, the data, or the information according to thedescriptions, functions, procedures, proposals, methods, and/oroperation flowcharts described in the present disclosure.

One or more processors 102 and 202 may be referred to as a controller, amicrocontroller, a microprocessor, or a microcomputer. One or moreprocessors 102 and 202 may be implemented by hardware, firmware,software, or a combination thereof. For example, one or more applicationspecific integrated circuits (ASICs), one or more digital signalprocessors (DSPs), one or more digital signal processing devices(DSPDs), one or more programmable logic devices (PLDs), or one or morefield programmable gate arrays (FPGAs) may be included in one or moreprocessors 102 and 202. The descriptions, functions, procedures,proposals, and/or operation flowcharts described in the presentdisclosure may be implemented by using firmware or software and thefirmware or software may be implemented to include modules, procedures,functions, and the like. Firmware or software configured to perform thedescriptions, functions, procedures, proposals, and/or operationflowcharts described in the present disclosure may be included in one ormore processors 102 and 202 or stored in one or more memories 104 and204 and driven by one or more processors 102 and 202. The descriptions,functions, procedures, proposals, and/or operation flowcharts describedin the present disclosure may be implemented by using firmware orsoftware in the form of a code, the instruction and/or a set form of theinstruction.

One or more memories 104 and 204 may be connected to one or moreprocessors 102 and 202 and may store various types of data, signals,messages, information, programs, codes, indications and/or instructions.One or more memories 104 and 204 may be comprised of a ROM, a RAM, anEPROM, a flash memory, a hard drive, a register, a cache memory, acomputer reading storage medium and/or a combination thereof. One ormore memories 104 and 204 may be positioned inside and/or outside one ormore processors 102 and 202. Further, one or more memories 104 and 204may be connected to one or more processors 102 and 202 through varioustechnologies such as wired or wireless connection.

One or more transceivers 106 and 206 may transmit to one or more otherdevices user data, control information, a wireless signal/channel, etc.,mentioned in the methods and/or operation flowcharts of the presentdisclosure. One or more transceivers 106 and 206 may receive from one ormore other devices user data, control information, a wirelesssignal/channel, etc., mentioned in the descriptions, functions,procedures, proposals, methods, and/or operation flowcharts described inthe present disclosure. For example, one or more transceivers 106 and206 may be connected to one or more processors 102 and 202 and transmitand receive the radio signals. For example, one or more processors 102and 202 may control one or more transceivers 106 and 206 to transmit theuser data, the control information, or the radio signal to one or moreother devices. Further, one or more processors 102 and 202 may controlone or more transceivers 106 and 206 to receive the user data, thecontrol information, or the radio signal from one or more other devices.Further, one or more transceivers 106 and 206 may be connected to one ormore antennas 108 and 208, and one or more transceivers 106 and 206 maybe configured to transmit and receive the user data, controlinformation, wireless signal/channel, etc., mentioned in thedescriptions, functions, procedures, proposals, methods, and/oroperation flowcharts described in the present disclosure through one ormore antennas 108 and 208. In the present disclosure, one or moreantennas may be a plurality of physical antennas or a plurality oflogical antennas (e.g., antenna ports). One or more transceivers 106 and206 may convert the received radio signal/channel from an RF band signalinto a baseband signal, in order to process the received user data,control information, radio signal/channel, etc., using one or moreprocessors 102 and 202. One or more transceivers 106 and 206 may convertthe user data, control information, radio signal/channel, etc.,processed using one or more processors 102 and 202, from the basebandsignal into the RF band signal. To this end, one or more transceivers106 and 206 may include an (analog) oscillator and/or filter.

Example of Signal Processing Circuit to which the Present Disclosure isApplied

FIG. 27 illustrates a signal processing circuit for a transmissionsignal.

Referring to FIG. 27 a signal processing circuit 1000 may include ascrambler 1010, a modulator 1020, a layer mapper 1030, a precoder 1040,a resource mapper 1050, and a signal generator 1060. Although notlimited thereto, an operation/function of FIG. 27 may be performed bythe processors 102 and 202 and/or the transceivers 106 and 206 of FIG.26. Hardware elements of FIG. 27 may be implemented in the processors102 and 202 and/or the transceivers 106 and 206 of FIG. 26. For example,blocks 1010 to 1060 may be implemented in the processors 102 and 202 ofFIG. 26. Further, blocks 1010 to 1050 may be implemented in theprocessors 102 and 202 of FIG. 26, and the block 1060 may be implementedin the transceivers 106 and 206 of FIG. 26.

A codeword may be transformed into a radio signal via the signalprocessing circuit 1000 of FIG. 27. The codeword is an encoded bitsequence of an information block. The information block may includetransport blocks (e.g., a UL-SCH transport block, a DL-SCH transportblock, etc.). The radio signal may be transmitted on various physicalchannels (e.g., PUSCH, PDSCH, etc).

Specifically, the codeword may be transformed into a bit sequencescrambled by the scrambler 1010. A scramble sequence used for scramblingmay be generated based on an initialization value, and theinitialization value may include ID information, etc. of a wirelessdevice. The scrambled bit sequence may be modulated into a modulatedsymbol sequence by the modulator 1020. A modulation scheme may includepi/2-binary phase shift keying (BPSK), m-phase shift keying (PSK),m-quadrature amplitude modulation (QAM), etc. A complex modulated symbolsequence may be mapped to one or more transport layers by the layermapper 1030. Modulated symbols of each transport layer may be mapped toa corresponding antenna port(s) by the precoder 1040 (precoding). Anoutput z of the precoder 1040 may be obtained by multiplying an output yof the layer mapper 1030 by a precoding matrix W of N*M, where N is thenumber of antenna ports, and M is the number of transport layers. Theprecoder 1040 may perform precoding after performing transform precoding(e.g., DFT transform) on complex modulated symbols. Further, theprecoder 1040 may perform the precoding without performing the transformprecoding.

The resource mapper 1050 may map the modulated symbols of each antennaport to time-frequency resources. The time-frequency resources mayinclude a plurality of symbols (e.g., CP-OFDMA symbol and DFT-s-OFDMAsymbol) in a time domain and include a plurality of subcarriers in afrequency domain. The signal generator 1060 may generate the radiosignal from the mapped modulated symbols, and the generated radio signalmay be transmitted to another device over each antenna. To this end, thesignal generator 1060 may include an inverse fast Fourier transform(IFFT) module, a cyclic prefix (CP) insertor, a digital-to-analogconverter (DAC), a frequency uplink converter, and the like.

A signal processing process for a received signal in the wireless devicemay be configured in the reverse of the signal processing processes(1010 to 1060) of FIG. 27. For example, the wireless device (e.g., 100and 200 of FIG. 26) may receive the radio signal from the outsidethrough the antenna port/transceiver. The received radio signal may beconverted into a baseband signal through a signal reconstructor. To thisend, the signal reconstructor may include a frequency downlinkconverter, an analog-to-digital converter (ADC), a CP remover, and aFast Fourier Transform (FFT) module. Thereafter, the baseband signal maybe reconstructed into the codeword through a resource de-mapper process,a postcoding process, a demodulation process, and a de-scramblingprocess. The codeword may be reconstructed into an original informationblock via decoding. Accordingly, a signal processing circuit (notillustrated) for the receive signal may include a signal reconstructer,a resource demapper, a postcoder, a demodulator, a descrambler, and adecoder.

Utilization Example of Wireless Device to which the Present Disclosureis Applied

FIG. 28 illustrates another example of a wireless device applied to thepresent disclosure. The wireless device may be implemented in varioustypes of devices according to usage examples/services.

Referring to FIG. 28, wireless devices 100 and 200 may correspond to thewireless devices 100 and 200 of FIG. 26 and may be comprised of variouselements, components, units, and/or modules. For example, the wirelessdevices 100 and 200 may include a communication unit 110, a control unit120, and a memory unit 130, and an additional element 140. Thecommunication unit may include a communication circuit 112 and atransceiver(s) 114. For example, the communication circuit 112 mayinclude one or more processors 102 and 202 and/or one or more memories104 and 204 of FIG. 26. For example, the transceiver(s) 114 may includeone or more transceivers 106 and 206 and/or one or more antennas 108 and208 of FIG. 26. The control unit 120 is electrically connected to thecommunication unit 110, the memory unit 130, and the additional element140 and controls an overall operation of the wireless device. Forexample, the control unit 120 may an electrical/mechanical operation ofthe wireless device based on a program/code/instruction/informationstored in the memory unit 130. Further, the control unit 120 maytransmit the information stored in the memory unit 130 to the outside(e.g., other communication devices) through the communication unit 110via a wireless/wired interface or store information received from theoutside (e.g., other communication devices) via the wireless/wiredinterface through the communication unit 110.

The additional element 140 may be variously configured according to thetype of wireless device. For example, the additional element 140 mayinclude at least one of a power unit/battery, an input/output (I/O)unit, a driving unit, and a computing unit. Although not limitedthereto, the wireless device may be implemented as a form such as therobot 100 a of FIG. 25, the vehicles 100 b-1 and 100 b-2 of FIG. 25, theXR device 100 c of FIG. 25, the portable device 100 d of FIG. 25, thehome appliance 100 e of FIG. 25, the IoT device 100 f of FIG. 25, adigital broadcasting terminal, a hologram device, a public safetydevice, an MTC device, a medical device, a FinTech device (or financialdevice), a security device, a climate/environment device, an AIserver/device 400 of FIG. 25, the base station 200 of FIG. 25, a networknode, etc. The wireless device may be movable or may be used at a fixedplace according to use examples/services.

In FIG. 28, all of various elements, components, units, and/or modulesin the wireless devices 100 and 200 may be interconnected via the wiredinterface or at least may be wirelessly connected through thecommunication unit 110. For example, the control unit 120 and thecommunication 110 in the wireless devices 100 and 200 may be wiredlyconnected and the control unit 120 and the first unit (e.g., 130 or 140)may be wirelessly connected through the communication unit 110. Further,each element, component, unit, and/or module in the wireless devices 100and 200 may further include one or more elements. For example, thecontrol unit 120 may be constituted by one or more processor sets. Forexample, the control unit 120 may be configured a set of a communicationcontrol processor, an application processor, an electronic control unit(ECU), a graphic processing processor, a memory control processor, etc.As another example, the memory unit 130 may be configured as a randomaccess memory (RAM), a dynamic RAM (DRAM), a read only memory (ROM), aflash memory, a volatile memory, a non-volatile memory, and/orcombinations thereof

Example of Portable Device to which the Present Disclosure is Applied

FIG. 29 illustrates a portable device applied to the present disclosure.

The portable device may include a smart phone, a smart pad, a wearabledevice (e.g., a smart watch, a smart glass), and a portable computer(e.g., a notebook, etc.). The portable device may be referred to as amobile station (MS), a user terminal (UT), a mobile subscriber station(MSS), a subscriber station (SS), an advanced mobile station (AMS), or awireless terminal (WT).

Referring to FIG. 29, a portable device 100 may include an antenna unit108, a communication unit 110, a control unit 120, a memory unit 130, apower supply unit 140 a, an interface unit 140 b, and an input/outputunit 140 c. The antenna unit 108 may be configured as a part of thecommunication unit 110. The blocks 110 to 130/140 a to 140 c correspondto the blocks 110 to 130/140 of FIG. 28, respectively.

The communication unit 110 may transmit/receive a signal (e.g., data, acontrol signal, etc.) to/from other wireless devices and base stations.The control unit 120 may perform various operations by controllingcomponents of the portable device 100. The control unit 120 may includean application processor (AP). The memory unit 130 may storedata/parameters/programs/codes/instructions required for driving theportable device 100. Further, the memory unit 130 may store input/outputdata/information, etc. The power supply unit 140 a may supply power tothe portable device 100 and include a wired/wireless charging circuit, abattery, and the like. The interface unit 140 b may support a connectionbetween the portable device 100 and another external device. Theinterface unit 140 b may include various ports (e.g., an audioinput/output port, a video input/output port) for the connection withthe external device. The input/output unit 140 c may receive or output avideo information/signal, an audio information/signal, data, and/orinformation input from a user. The input/output unit 140 c may include acamera, a microphone, a user input unit, a display 140 d, a speaker,and/or a haptic module.

For example, in the case of data communication, the input/output unit140 c may acquire information/signal (e.g., touch, text, voice, image,video, etc.) input from the user, and the acquired information/signalmay be stored in the memory unit 130. The communication unit 110 maytransform the information/signal stored in the memory into the radiosignal and directly transmit the radio signal to another wireless deviceor transmit the radio signal to the base station. Further, thecommunication unit 110 may receive the radio signal from anotherwireless device or base station and then reconstruct the received radiosignal into original information/signal. The reconstructedinformation/signal may be stored in the memory unit 130 and then outputin various forms (e.g., text, voice, image, video, haptic) through theinput/output unit 140 c.

Example of Robot to which the Present Disclosure is Applied

FIG. 30 illustrates a robot applied to the present disclosure. The robotmay be classified for industry, medical treatment, home, and militarybased on its use purpose or field.

Referring to FIG. 30, a robot 100 may include a communication unit 110,a control unit 120, a memory unit 130, an input/output unit 140 a, asensor unit 140 b, and a driving unit 140 c. The blocks 110 to 130/140 ato 140 c correspond to the blocks 110 to 130/140 of FIG. 28,respectively.

The communication unit 110 may transmit/receive signals (e.g., drivinginformation, control signals, etc.) to/from external devices such asother wireless devices, robots, or control servers. The control unit 120may perform various operations by controlling the components of therobot 100. The memory unit 130 may storedata/parameters/programs/codes/instructions supporting various functionsof the robot 100. The input/output unit 140 a may acquire informationfrom the outside of the robot 100 and output information to the outsideof the robot 100. The input/output unit 140 a may include a camera, amicrophone, a user input unit, a display, a speaker, and/or a hapticmodule, or the like. The sensor unit 140 b may obtain internalinformation, surrounding environment information, user information, etc.of the robot 100. The sensor unit 140 b may include a proximity sensor,an illumination sensor, an acceleration sensor, a magnetic sensor, agyro sensor, an inertia sensor, an IR sensor, a fingerprint recognitionsensor, an ultrasonic sensor, a photo sensor, a microphone, and a radar.The driving unit 140 c may perform various physical operations, such asmoving a robot joint. Furthermore, the driving unit 140 c may allow therobot 100 to run on the ground or fly in the air. The driving unit 140 cmay include an actuator, a motor, a wheel, a brake, a propeller, etc.

INDUSTRIAL APPLICABILITY

Although the present disclosure has been described focusing on examplesapplying to the 3GPP LTE/LTE-A/NR system, it can be applied to variouswireless communication systems other than the 3GPP LTE/LTE-A/NR system.

1. A method for controlling, by a user equipment (UE), a transmit powerin a narrowband (NB) wireless communication system, the methodcomprising: receiving, from a base station, information related toDiscontinuous Reception, DRX, using Radio Resource Control, RRC,signaling, receiving, from the base station, a paging message based onthe information related to DRX, transmitting, to the base station, aPhysical Random Access Channel, PRACH, preamble based on the pagingmessage, receiving, from the base station, a random access responseincluding Uplink, UL, grant based on the PRACH preamble, transmitting,to the base station, message 3 based on the UL grant, receiving, fromthe base station, a message for contention resolution based on themessage 3, receiving, from the base station, a preconfigured uplink (UL)resource (PUR) configuration; transmitting, to the base station, uplinkdata on the PUR; and receiving, from the base station, feedbackinformation for the uplink data, wherein the feedback information isconfigured to be received on an NPDCCH after a specific time has passedfrom the PUR transmission. 2-10. (canceled)
 11. The method of claim 1,wherein a transmit power of the uplink data is controlled based on anumber of receptions of the feedback information.
 12. The method ofclaim 11, wherein a ramping interval of the transmit power is indicatedfrom the base station.
 13. The method of claim 11, wherein the UEtransmits the uplink data in an idle mode, wherein the transmit power isa transmit power used in a connected mode with the base station beforeentering the idle mode.
 14. The method of claim 11, wherein a specificoffset value is added to a current transmit power.
 15. The method ofclaim 11, wherein the transmit power of the uplink data is controlledbased on a number of transmissions of the uplink data.
 16. A userequipment (UE) controlling a transmit power in a narrowband (NB)wireless communication system, the UE comprising: a radio frequency (RF)module configured to transmit and receive a radio signal; and aprocessor functionally connected to the RF module, wherein the processoris configured to: receive, from a base station, information related toDiscontinuous Reception, DRX, using Radio Resource Control, RRC,signaling, receive, from the base station, a paging message based on theinformation related to DRX, transmit, to the base station, a PhysicalRandom Access Channel, PRACH, preamble based on the paging message,receive, from the base station, a random access response includingUplink, UL, grant based on the PRACH preamble, transmit, to the basestation, message 3 based on the UL grant, receive, from the basestation, a message for contention resolution based on the message 3,receive, from the base station, a preconfigured uplink (UL) resource(PUR) configuration; transmit, to the base station, uplink data on thePUR; and receive, from the base station, feedback information for theuplink data, wherein the feedback information is configured to bereceived on an NPDCCH after a specific time has passed from the PURtransmission.
 17. The UE of claim 16, wherein a transmit power of theuplink data is controlled based on a number of receptions of thefeedback information.
 18. The UE of claim 17, wherein the processorreceives, from the base station, an indication of a ramping interval ofthe transmit power.
 19. The UE of claim 17, wherein the processortransmits the uplink data in an idle mode, wherein the transmit power isa transmit power used in a connected mode with the base station beforeentering the idle mode.
 20. The UE of claim 17, wherein the processoradds a specific offset value to a current transmit power.
 21. The UE ofclaim 17, wherein the processor controls the transmit power of theuplink data based on a number of transmissions of the uplink data.
 22. Amethod for controlling, by a base station, a transmit power in anarrowband (NB) wireless communication system, the method comprising:transmitting, to a user equipment, UE, information related toDiscontinuous Reception, DRX, using Radio Resource Control, RRC,signaling, transmitting, to the UE, a paging message based on theinformation related to DRX, receiving, from the UE, a Physical RandomAccess Channel, PRACH, preamble based on the paging message,transmitting, to the UE, a random access response including Uplink, UL,grant based on the PRACH preamble, receiving, from the UE, message 3based on the UL grant, transmitting, to the UE, a message for contentionresolution based on the message 3, transmitting, to the UE, apreconfigured uplink (UL) resource (PUR) configuration; receiving, fromthe UE, uplink data on the PUR; and transmitting, to the UE, feedbackinformation for the uplink data, wherein the feedback information isconfigured to be transmitted on an NPDCCH after a specific time haspassed from the PUR reception.
 23. The method of claim 22, wherein atransmit power of the uplink data is controlled by the UE based on anumber of transmissions of the feedback information by the base station.24. The method of claim 23, wherein a ramping interval of a transmitpower of the UE is indicated from the base station.